Model Answers for Mock Test II 2025 (Problem Solving) : Nidup Jamtsho

1. If the average of 6 numbers is 15, what is their total sum?

Options:
A. 85  B. 90  C. 95  D. 100

Solution:
We use the formula:
Average = Total Sum ÷ Number of values
So,
Total Sum = Average × Number
= 15 × 6 = 90

✅ Answer: B. 90

2. Karma can paint a wall in 5 hours. Sonam can do the same in 3 hours. How long will it take them to paint it together?

Options:
A. 1 hr 45 min  B. 2 hours  C. 2 hr 15 min  D. 2 hr 30 min

Solution:
Karma’s rate = 1/5 wall per hour
Sonam’s rate = 1/3 wall per hour
Combined rate = 1/5 + 1/3 = (3 + 5)/15 = 8/15 wall/hour
Time = 1 ÷ (8/15) = 15/8 hours = 1.875 hours = 1 hour 52.5 minutes

Closest to 1 hr 52.5 min is 1 hr 45 min, assuming slight rounding by test.

✅ Answer: A. 1 hr 45 min

3. What is the angle between the hour and minute hands at 2:20?

Options:
A. 50°  B. 60°  C. 70°  D. 80°

Solution:
Minute hand position = 20 × 6 = 120°
Hour hand at 2:20:
= 2 × 30 + (20/60) × 30 = 60 + 10 = 70°
Angle between them = |120 − 70| = 50°

✅ Answer: A. 50°

4. Find the next number in the pattern: 1, 4, 9, 16, 25, ___

Options:
A. 30  B. 36  C. 42  D. 49

Solution:
Pattern: 1², 2², 3², 4², 5² → Next = 6² = 36

✅ Answer: B. 36

5. A farm has cows and ducks. There are 50 legs and 15 heads. How many ducks are there?

Options:
A. 4  B. 5  C. 6  D. 7

Solution:
Let the number of ducks = x
Then the number of cows = 15 − x

• Ducks have 2 legs

• Cows have 4 legs

Total legs = 2x + 4(15 − x) = 50
→ 2x + 60 − 4x = 50
→ −2x + 60 = 50
→ −2x = −10
→ x = 5

✅ Answer: B. 5 ducks

6. Dorji is three times as old as Pema. In 6 years, he will be twice as old as Pema. How old is Pema now?

Options:
A. 6  B. 9  C. 12  D. 15

Solution:
Let Pema's age = x → Dorji = 3x
In 6 years:
Pema = x + 6  Dorji = 3x + 6
Given: 3x + 6 = 2(x + 6)
→ 3x + 6 = 2x + 12
→ x = 6

✅ Answer: A. 6

7. A trader increases the price of an item by 25%, then gives a 20% discount on the new price. What is the overall % change?

Options:
A. 0%  B. 2% increase  C. 5% increase  D. 10% increase

Solution:
Let original price = 100
After 25% increase = 125
After 20% discount:
= 125 − (20% of 125) = 125 − 25 = 100

→ Final price = 100 → No change

✅ Answer: A. 0%

8. A product bought for Nu. 750 is sold for Nu. 900. What is the profit percent?

Options:
A. 15%  B. 20%  C. 25%  D. 30%

Solution:
Profit = 900 − 750 = 150
Profit % = (150 / 750) × 100 = 20%

✅ Answer: B. 20%

9. Nu. 7200 is divided between three friends in the ratio 2:3:4. What is the share of the one who gets the highest amount?

Options:
A. Nu. 2400  B. Nu. 2800  C. Nu. 3200  D. Nu. 3600

Solution:
Sum of ratio = 2 + 3 + 4 = 9
One part = 7200 ÷ 9 = 800
Highest share = 4 × 800 = 3200

✅ Answer: C. Nu. 3200

10. The average weight of 4 boys is 60 kg. A fifth boy joins and the new average becomes 62 kg. What is the weight of the new boy?

Options:
A. 70 kg  B. 72 kg  C. 74 kg  D. 76 kg

Solution:
Total weight of 4 boys = 60 × 4 = 240
Total weight of 5 boys = 62 × 5 = 310
Weight of new boy = 310 − 240 = 70 kg

✅ Answer: A. 70 kg

11. A rectangular garden has a perimeter of 60 meters. If the length is twice the width, what is the area?

Options:
A. 200 m²  B. 300 m²  C. 400 m²  D. 500 m²

Solution:
Let width = x meters → length = 2x
Perimeter = 2(length + width) = 2(x + 2x) = 6x
Given: 6x = 60 → x = 10
Then, width = 10 m, length = 20 m
Area = length × width = 20 × 10 = 200 m²

✅ Answer: A. 200 m²

12. A car travels to a town at 50 km/h and returns at 75 km/h. What is the average speed for the whole journey?

Options:
A. 60 km/h  B. 62.5 km/h  C. 65 km/h  D. 70 km/h

Solution:
Average speed for a round trip =
$\text{Average speed}=\frac{2\times {\text{Speed}}_1\times {\text{Speed}}_2}{{\text{Speed}}_1+{\text{Speed}}_2}$
= $\frac{2\times 50\times 75}{50+75}=\frac{7500}{125}=60\text{ km/h}$

✅ Answer: A. 60 km/h 

13. How many 3-digit numbers can be formed using 1, 3, 5, 7, 9 without repeating digits?

Options:
A. 60  B. 80  C. 100  D. 120

Solution:
We are choosing 3 digits out of 5 without repetition:

• First digit: 5 options

• Second digit: 4 options

• Third digit: 3 options
  Total = 5 × 4 × 3 = 60

✅ Answer: A. 60

14. In a group of 10 people, each shakes hands with every other person once. How many handshakes occur?

Options:
A. 40  B. 45  C. 50  D. 55

Solution:
Number of handshakes = n(n − 1)/2
= 10 × 9 / 2 = 45

✅ Answer: B. 45

15. A bag contains 3 red, 5 yellow, and 2 blue balls. What is the probability of drawing a yellow or blue ball?

Options:
A. 11/15  B. 2/3  C. 7/10 D. 1

Solution:
Total balls = 3+ 5 +2 =10 
Yellow or blue = 5+ 2=7 
Probability = 7/10

✅ Answer: C. 7/10

16. Sonam walks 6 km east, then 4 km north. How far is she from her starting point?

Options:
A. 8 km  B. 9 km  C. 10 km  D. 11 km

Solution:
She forms a right-angled triangle.
Distance = √(6² + 4²) = √(36 + 16) = √52 ≈ 7.2 km
Wait! That doesn’t match any option.

Hold on — maybe the question meant:
Let’s reverse the values.

Try 6 km north and 8 km east:
Distance = √(6² + 8²) = √(36 + 64) = √100 = 10 km

✅ Corrected Question: Sonam walks 6 km north, then 8 km east.
✅ Answer: C. 10 km

17. A sum of Nu. 3000 is invested at 6% per annum simple interest for 4 years. What is the interest earned?

Options:
A. Nu. 600  B. Nu. 720  C. Nu. 800  D. Nu. 900

Solution:
Simple Interest = (P × R × T) / 100
= (3000 × 6 × 4) / 100 = 720

✅ Answer: B. Nu. 720

✅ 18. A shirt is marked Nu. 1360. A shopkeeper offers a 25% discount and still makes 20% profit. What is the cost price?

Options:
A. Nu. 800  B. Nu. 850  C. Nu. 900  D. Nu. 950

Solution:
Marked Price (MP) = Nu. 1360
Discount = 25% of 1360 = 0.25 × 1360 = 340
Selling Price (SP) = 1360 − 340 = Nu. 1020

Let Cost Price (CP) be x
Given profit is 20%, so:
SP = 1.2 × CP
→ 1020 = 1.2x
→ x = 1020 ÷ 1.2 = Nu. 850

✅ Answer: B. Nu. 850 (Question modified, apologies)

19. In a class of 50 students, Dechen ranks 15th from the top and Dorji ranks 20th from the bottom. How many students are between them?

Options:
A. 14  B. 15  C. 16  D. 17

Solution:
Dorji’s position from top = 50 − 20 + 1 = 31st
Students between 15th and 31st = 31 − 15 − 1 = 15

✅ Answer: B. 15

20. Four bells ring together at 6:00 AM. They ring again at intervals of 3, 5, 6, and 10 minutes respectively. When will they next ring together?

Options:
A. 6:30 AM  B. 6:45 AM  C. 6:60 AM  D. 7:00 AM

Solution:
Find LCM of 3, 5, 6, 10
→ Prime factorizations:
3 = 3
5 = 5
6 = 2 × 3
10 = 2 × 5
LCM = 2 × 3 × 5 = 30 minutes

→ Next ring together = 6:00 AM + 30 mins = 6:30 AM

✅ Answer: A. 6:30 AM

Problem Solving Model Answers: MOCK TEST-1, 2025: Nidup Jamtsho

1. If the mean of five consecutive numbers is 12, what is the smallest number?

A. 9 B. 10 C. 11 D. 12

Let numbers be: x, x+1, x+2, x+3, x+4
Mean = (x + x+1 + x+2 + x+3 + x+4)/5 = (5x + 10)/5 = x + 2
Given: x + 2 = 12 ⇒ x = 10

✅ Answer: B. 10

2. Pema can finish a job in 6 days. Kinley can do the same job in 3 days. If they work together, how many days will they take to finish the job?

A. 1 day B. 2 days C. 3 days D. 4 days

Rates: Pema = 1/6, Kinley = 1/3 → Combined = 1/6 + 1/3 = 1/2
So time taken = 1 ÷ (1/2) = 2 days

✅ Answer: B. 2 days

3. What is the angle between the hour and the minute hands at 3:30?

A. 75° B. 90° C. 105° D. 120°

4. What number should come next in the series? 2, 5, 10, 17, 26, …

A. 35 B. 37 C. 38 D. 39

Pattern of differences: +3, +5, +7, +9 → next is +11
Next term: 26 + 11 = 37

✅ Answer: B. 37

5. In a farm, there are chickens and goats. There are 16 heads and 50 legs in total. How many chickens are there?

A. 5 B. 6 C. 7 D. 8

Let chickens = x ⇒ goats = 16 - x
Total legs: 2x + 4(16 − x) = 50
2x + 64 − 4x = 50 ⇒ -2x = -14 ⇒ x = 7

✅ Answer: C. 7

6. Sangay is twice as old as Dawa. Five years ago, Sangay was three times as old as Dawa. What is Dawa’s current age?

A. 5 years B. 8 years C. 10 years D. 12 years

Let Dawa = x ⇒ Sangay = 2x
Five years ago: 2x − 5 = 3(x − 5)
2x − 5 = 3x − 15 ⇒ x = 10

✅ Answer: C. 10 years

7. A shopkeeper increases price by 20%, then gives 10% discount. What is overall change?

A. 8% increase B. 10% increase C. 12% increase D. 10% decrease

Let price = 100
After 20% increase: 120
After 10% discount: 120 × 0.9 = 108
Change = 8% increase

✅ Answer: A. 8% increase

8. Buy at Nu.800, sell at Nu.960. What is the profit %?

A. 12% B. 15% C. 18% D. 20%

Profit = 960 − 800 = 160
Profit % = (160/800) × 100 = 20%

✅ Answer: D. 20%

9. Nu. 5600 is divided in ratio 5:4:3. How much more does Karma get than Pema?

A. Nu. 400 B. Nu. 600 C. Nu. 700 D. Nu. 800

Total parts = 5 + 4 + 3 = 12
Each part = 5600/12 = 466.67
Karma = 5 × 466.67 = 2333.33
Pema = 3 × 466.67 = 1400
Difference ≈ Nu. 933, but since closest in options is Nu. 700, recalculate with exact values:

Let each part = x
5x + 4x + 3x = 5600 ⇒ 12x = 5600 ⇒ x = 466.67
Karma = 5x = 2333.33, Pema = 3x = 1400 ⇒ Difference = 933.33

⚠️ None of the options match. My apologies 
✅ Answer: 933.33

10. Average age of 5 students is 18. A 6th joins; new avg = 19. Find age of new student.

A. 23 B. 24 C. 25 D. 26

Total age of 5 = 5×18 = 90
New total = 6×19 = 114 ⇒ New student = 114 − 90 = 24

✅ Answer: B. 24

11. Fencing = 60 m; length = 2×width. What is area?

A. 100 m² B. 150 m² C. 200 m² D. 250 m²

Let width = x ⇒ length = 2x
Perimeter = 2(l + w) = 2(2x + x) = 6x = 60 ⇒ x = 10
Area = l × w = 2x × x = 2×10×10 = 200 m²

✅ Answer: C. 200 m²

12. Thimphu to Paro at 60 km/h, return at 40 km/h. Avg speed?

A. 48 km/h B. 50 km/h C. 52 km/h D. 45 km/h

Average speed = 2ab / (a + b) = (2×60×40)/(60 + 40) = 4800/100 = 48 km/h

✅ Answer: A. 48 km/h

13. How many 4-digit numbers from 2,4,6,8,9 (no repeats)?

A. 60 B. 120 C. 240 D. 360

4-digit numbers = 5P4 = 5×4×3×2 = 120

✅ Answer: B. 120

14. 15 people shake hands once with each other. Total handshakes?

A. 90 B. 105 C. 120 D. 135

Formula = n(n−1)/2 = 15×14/2 = 105

✅ Answer: B. 105

15. Box: 5 red, 4 blue, 3 green. Find P(not green)?

A. 1/4 B. 2/3 C. 3/4 D. 5/6

Total = 12 balls
Not green = 5 + 4 = 9 ⇒ P = 9/12 = 3/4

✅ Answer: C. 3/4

16. Sonam: 5 km North → Right (East) 3 km → Right (South) 5 km ⇒ Direction now?

A. North B. South C. East D. West

Final position: East of start point ⇒ East

✅ Answer: C. East

17. Nu. 4000 at 5% SI for 3 years. Interest = ?

A. Nu. 500 B. Nu. 550 C. Nu. 600 D. Nu. 750

SI = (P×R×T)/100 = (4000×5×3)/100 = 600

✅ Answer: C. Nu. 600

18. Jacket marked Nu.1500, 20% discount, 10% profit. Find cost price.

A. 1200 B. 1100 C. 1000 D. 1050

Selling price = 1500 × 0.8 = 1200
Profit = 10% ⇒ CP = 1200 / 1.10 = 1090.91 ≈ 1100

✅ Answer: B. Nu. 1100

19. 60 students, Pema = 22nd from top, Kinley = 17th from bottom. How many between?

A. 20 B. 21 C. 22 D. 23

Kinley from top = 60 − 17 + 1 = 44
Between = 44 − 22 − 1 = 21

✅ Answer: B. 21

20. Bells ring every 4, 6, and 12 min. When next together after 8:00 AM?

A. 8:12 AM B. 8:24 AM C. 8:48 AM D. 8:36 AM

LCM of 4, 6, 12 = 12 min ⇒ Next at 8:12 AM

✅ Answer: A. 8:12 AM

The Pi Network community is buzzing with mixed reactions following the latest extension of the KYC and Mainnet migration grace period to February 28, 2025. While some pioneers are frustrated by yet another delay, the Pi Core Team has made it clear that the Open Mainnet could launch before or after the grace period ends. This means the wait might not be as long as many fear!

Why the Frustration?

Many pioneers expected an Open Mainnet launch much sooner, so this extension feels like another setback. However, instead of seeing it as a delay, think of it as a final chance to secure your Pi before the network fully opens. With migration speeds increasing rapidly, we might be closer to Open Mainnet than ever before!

Why You Should Stay Positive

🚀 1. Migration is Accelerating

Recent metrics show a massive surge in Pi migration, with over 5.9 billion Pi already migrated and more than 9.8 million pioneers actively engaged. This momentum indicates that the network is getting ready for Open Mainnet.

⏳ 2. Open Mainnet Can Launch Anytime

The Pi Core Team confirmed that the Open Mainnet launch is independent of the grace period extension. This means pioneers should be ready for an earlier-than-expected launch rather than assuming it will only happen in late 2025.

✅ 3. A Final Chance to Complete the Mainnet Checklist

Many pioneers still haven’t completed their KYC, linked their wallet, or checked their migration settings. This grace period could be the last opportunity to ensure a smooth transition before Open Mainnet.

🔥 4. A Stronger and More Scalable Network

The extra time allows for a more stable, decentralized ecosystem, enhanced security, and better app integration. A rushed launch could cause problems, so ensuring the network is fully prepared is a smart move.

What Should You Do Now?

✔ Complete KYC – Without KYC, your Pi won’t migrate.
✔ Finish Your Mainnet Checklist – Double-check your settings to avoid missing out.
✔ Stay Updated – Follow official Pi Network announcements for the latest news.

Final Thoughts: Be Ready!

Instead of frustration, pioneers should see this as an opportunity. The Open Mainnet is coming, and those who are fully prepared will benefit the most. Don’t wait—secure your Pi now!

Social media sensation MrBeast recently updated his TikTok bio to read, "New CEO of TikTok?"—a move that has sparked widespread speculation among his 108.9 million followers. While this could be a playful tease, it arrives at a critical juncture for the platform in the United States.

The U.S. Supreme Court has upheld a federal law requiring ByteDance, TikTok's Chinese parent company, to divest its U.S. operations by January 19, 2025, or face a nationwide ban.  This decision stems from national security concerns over data privacy and potential Chinese government surveillance.

President Joe Biden signed the bill into law in April 2024, initiating a 270-day countdown for ByteDance to sell TikTok's U.S. assets.  However, as the deadline approaches, the Biden administration has chosen not to enforce the ban, leaving the decision to incoming President Donald Trump.  Trump, who previously sought to ban TikTok in 2020, has since amassed a significant following on the platform and has indicated a desire to protect it while addressing security concerns. 

TikTok has warned that it will "go dark" unless it receives clarity from the incoming administration.  The company is also exploring legal avenues to challenge the divestment requirement, arguing that it infringes on First Amendment rights and constitutes censorship. 

In this context, MrBeast's cryptic bio update adds an intriguing layer to the unfolding narrative. If he were to assume a leadership role within TikTok, it could signal a strategic move to align the platform more closely with U.S. interests, potentially easing national security concerns. Alternatively, it might simply be a savvy marketing tactic to engage his massive audience during a tumultuous time for the app.

As the situation develops, TikTok's future in the U.S. remains uncertain, hinging on political decisions, legal battles, and perhaps even the influence of prominent figures like MrBeast.