1. 3, 5, 13, 43, 178, 891, 5353
A. 43
B. 178
C. 891
D. 5353
E. None of these
Answer: Option B
Explanation:
3 × 1 + 2 = 5
5 × 2 + 3 = 13
13 × 3 + 4 = 43…..
Correct Number: 177
2. There are 4 filling pipes and 3 emptying pipes capable of filling and emptying in 12 minutes and 15 minutes respectively. If all the pipes are opened together and as a result they fill 10 litres of water per minute. Find the capacity of the tank.
A. 65 ltr
B. 70 ltr
C. 75 ltr
D. 80 ltr
E. None of these
Answer: Option C
Explanation:
([latex]\frac{4}{12}[/latex] - [latex]\frac{3}{15}[/latex]) × t = 1
t = [latex]\frac{15}{2}[/latex] minute – in this time the tank will be filled. So the capacity = [latex]\frac{15}{2}[/latex] × 10 = 75 litre
3. Ronit's age is 10 years more than Rohit's age. Also Ronit was twice old as Rohit 15 years ago. What will be the age of Ronit 6 years after?
A. 41
B. 40
C. 35
D. 45
E. 38
Answer: Option A
Explanation:
Rohit = x, Ronit = x+10
(x + 10) – 15 = 2 (x – 15)
Solve, x = 25
Ronit's 6 years after = x + 10 + 6
= 41
4. Ashwin has to travel from one point to another point in a certain time. Travelling at a speed of 6kmph he reaches 40m late and travelling at a speed of 8kmph he reaches 12 m earlier. What is the distance between this two points ?
A. 27 km
B. 18 km
C. 5 km
D. 21 km
E. None of these
Answer: Option D
Explanation:
[latex]\frac{d}{6}[/latex] - [latex]\frac{40}{60}[/latex] = [latex]\frac{d}{8}[/latex] + [latex]\frac{12}{60}[/latex]
[latex]\frac{d}{6}[/latex] - [latex]\frac{d}{8}[/latex] = [latex]\frac{12}{60}[/latex] - [latex]\frac{40}{60}[/latex]
[latex]\frac{2d}{48}[/latex] = [latex]\frac{52}{60}[/latex]
D= 52 × [latex]\frac{40}{60}[/latex] × 2 = 20.8 = 21km
5. The average age of the group having 3 members is 84. One more person joins the group and now the average becomes 80. Now a fifth person comes whose age is 3 years more than that of fourth person replaces the first person. After this the average age of the group becomes 79. What is the weight of the first person?
A. 75
B. 65
C. 68
D. 82
E. 85
Answer: Option A
Explanation:
Let the ages of these are A, B, C, D, E
So A + B + C = 84 × 3 = 252
And A + B + C + D = 80 × 4 = 320
So D = 320 – 252 = 68, so E = 68 + 3 = 71
Now B + C + D + E = 79 × 4 = 316
(A + B + C + D) – (B + C + D + E) = 320 – 316
So A – E = 4, so A = 71 + 4