A train travels 120 km in 2 hours and then 150 km in 3 hours. What is the average speed of the train?
Total distance = 120 + 150 = 270 km. Total time = 2 + 3 = 5 hours. Average speed = 5270 = 54 km/h
If a number is divisible by both 12 and 18, it must be divisible by:
LCM of 12 and 18 = 36. Any number divisible by both 12 and 18 must be divisible by their LCM, which is 36
What is the compound interest on Rs. 10,000 at 10% per annum for 2 years?
CI = P[(1 + r/100)^n - 1] = 10000[(1.1)^2 - 1] = 10000[0.21] = Rs. 2,100
If 5 workers can complete a job in 12 days, how many days will 8 workers take?
Work = 5 × 12 = 60 worker-days. Days for 8 workers = 860 = 7.5 days
A shopkeeper buys an item at Rs. 400 and sells it at Rs. 520. What is his profit percentage?
Profit = 520 - 400 = 120. Profit% = (400120) × 100 = 30%
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What is the missing number in the series: 2, 6, 12, 20, ?, 42
Series follows n(n+1): 1×2=2, 2×3=6, 3×4=12, 4×5=20, 5×6=30, 6×7=42
If a:b = 3:4 and b:c = 5:6, then a:b:c is:
a:b = 3:4, b:c = 5:6. Multiply first by 5 and second by 4: a:b = 15:20, b:c = 20:24. So a:b:c = 15:20:24
In a class of 50 students, 30 study Math and 25 study Science. How many study both?
Using set theory: n(M∪S) = n(M) + n(S) - n(M∩S). 50 = 30 + 25 - n(M∩S). n(M∩S) = 5
What is the value of (2.5)² - (1.5)² / 2?
(2.5)² - (1.5)² / 2 = [6.25 - 2.25] / 2 = 24 = 2
If x² + 1/x² = 7, then x + 1/x is:
(x + 1/x)² = x² + 2 + 1/x² = 7 + 2 = 9. So x + 1/x = ±3
Which number is NOT a perfect square?
144=12², 169=13², 196=14², but 195 is not a perfect square (√195 ≈ 13.96)
Find the next number in the sequence: 1, 1, 2, 3, 5, 8, ?
This is the Fibonacci sequence where each number is the sum of the previous two: 5+8=13
If 30% of x is 45, then x is:
0.30 × x = 45. x = 045.30 = 150
A man walks 5 km north, then 3 km east, then 5 km south. How far is he from his starting point?
After north and south movements (cancel out), he is only 3 km east of starting point
What is the angle between the hour hand and minute hand at 3:15?
At 3:15, minute hand at 3 (90°), hour hand at 3 + 6015 × 30 = 97.5°. Difference = 7.5°
All cats are animals. All animals breathe. Therefore:
This is deductive reasoning. If cats are animals and animals breathe, then cats must breathe
Statement: Some doctors are teachers. All teachers are educated. Conclusion: Some doctors are educated.
Since some doctors are teachers, and all teachers are educated, some doctors must be educated
If ROSE is coded as 6918, then NOSE is coded as:
R=6, O=9, S=1, E=8. So NOSE = 1-9-1-8 = 1918
If ORANGE is to FRUIT, then SHARK is to:
Orange is a type of fruit. Shark is a type of fish. This is a classification relationship
Look at this sequence: AZ, BY, CX, DW, ?
First letter advances (A→B→C→D→E), second letter reverses (Z→Y→X→W→V)
