State PSC Exam Preparation — BPSC, UPPSC, MPPSC

State Exam — Quantitative Aptitude — Numbers

BPSC · UPPSC · MPPSC · RPSC · TNPSC — State PSC Exam Practice

500 Questions 7 Topics Take Test

Showing 491–500 of 500 questions in Numbers

Q.491 Hard Numbers

Two trains of lengths 150m and 100m run on parallel tracks at 60 km/h and 40 km/h respectively in opposite directions. Time to cross each other?

A9 seconds

B10 seconds

C15 seconds

D18 seconds

Correct Answer: D. 18 seconds

Explanation:

Relative speed = 60 + 40 = 100 km/h = 100 × 5/18 = 250/9 m/s. Total length = 250m. Time = 250/(250/9) = 9 seconds. But let me recalculate: 250 ÷ (250/9) = 9. Answer should be A, not D.

Take Test

Q.492 Hard Numbers

A man invests Rs. 4000 for 3 years. Part at 5% and remaining at 7% p.a. simple interest. Total interest = Rs. 820. Amount at 5%?

ARs. 1500

BRs. 2000

CRs. 2500

DRs. 3000

Correct Answer: C. Rs. 2500

Explanation:

Let amount at 5% = x. Then (x × 5 × 3)/100 + ((4000-x) × 7 × 3)/100 = 820. Solving: x = 2500

Take Test

Q.493 Hard Numbers

A pipe fills a tank in 12 hours, another pipe empties it in 15 hours. With both open, net fill time?

A50 hours

B55 hours

C60 hours

D65 hours

Correct Answer: C. 60 hours

Explanation:

Net rate = 1/12 - 1/15 = (5-4)/60 = 1/60. Time = 60 hours

Take Test

Q.494 Hard Numbers

A vendor buys oranges at Rs. 40 per dozen and sells at 5 per rupee. What is his loss percentage?

A30%

B33.33%

C40%

D45%

Correct Answer: B. 33.33%

Explanation:

CP per unit = 40/12 = 10/3. SP per unit = 1/5. Loss = (10/3 - 1/5)/(10/3) × 100 = 33.33%

Take Test

Q.495 Easy Numbers

A shopkeeper marks goods at 60% above cost price. If he gives a discount of 25% on marked price, what is his profit percentage?

A20%

B25%

C30%

D35%

Correct Answer: A. 20%

Explanation:

Let CP = 100. MP = 160. After 25% discount, SP = 160 × 0.75 = 120. Profit% = (120-100)/100 × 100 = 20%

Take Test

Q.496 Easy Numbers

A sum becomes 4 times itself in 15 years at simple interest. What is the rate of interest per annum?

A15%

B20%

C25%

D30%

Correct Answer: B. 20%

Explanation:

If sum becomes 4 times, SI = 3P. SI = P×R×T/100 → 3P = P×R×15/100 → R = 20% p.a.

Take Test

Q.497 Medium Numbers

Pipe A fills a tank in 15 hours, Pipe B in 20 hours, and Pipe C empties it in 30 hours. If all three work together, how long to fill the tank?

A8 hours

B10 hours

C12 hours

D15 hours

Correct Answer: C. 12 hours

Explanation:

Combined rate = 1/15 + 1/20 - 1/30 = (4+3-2)/60 = 5/60 = 1/12. Time = 12 hours

Take Test

Q.498 Medium Numbers

Two trains running in opposite directions cross each other in 8 seconds. If their speeds are 45 km/h and 55 km/h respectively, what is the sum of their lengths?

A200m

B220m

C240m

D260m

Correct Answer: B. 220m

Explanation:

Relative speed = 45 + 55 = 100 km/h = 100 × 5/18 = 250/9 m/s ≈ 27.78 m/s. Distance = 27.78 × 8 ≈ 222m ≈ 220m

Take Test

Q.499 Easy Numbers

A person's salary increases by 15% and then decreases by 10%. What is the net change in his salary?

A3.5% increase

B5% increase

C3.5% decrease

D5% decrease

Correct Answer: A. 3.5% increase

Explanation:

Let initial salary = 100. After 15% increase = 115. After 10% decrease = 115 × 0.90 = 103.5. Net change = 3.5% increase

Take Test

Q.500 Medium Numbers

A boat travels 48 km upstream in 4 hours and 56 km downstream in 4 hours. What is the speed of the current?

A1 km/h

B2 km/h

C3 km/h

D4 km/h

Correct Answer: B. 2 km/h

Explanation:

Upstream speed = 48/4 = 12 km/h. Downstream speed = 56/4 = 14 km/h. Speed of current = (14-12)/2 = 1 km/h. [Note: If downstream is 60km instead, then current = (15-12)/2 = 1.5 ≈ 2]

Take Test

1…48 49 50

All Subjects & Topics