Aptitude test for Teachers - Set 3

1)   How many combinations are possible while selecting four letters from the word ‘SMOKEJACK’ with the condition that ‘J’ must appear in it?

a. 81
b. 8!/2!
c. 3!/2!
d. 41
Answer  Explanation 

ANSWER: 41

Explanation:
permutation combination


2)   A and B are standing on ground 50 meters apart. The angles of elevation for these two to the top of a tree are 60° and 30°. What is height of the tree?

a. 503 m
b. 25/3 m
c. 253 m
d. 25/(3-1) m
Answer  Explanation 

ANSWER: 253 m

Explanation:
height and distance


3)   There is a leak at the bottom of a cistern. Due to this it takes 8 hours to fill the cistern. Had there not been a leak, it would take one hour less to fill the cistern. How much time does it take for the leak to completely empty the cistern?

a. 48 hours
b. 55(1/3) hours
c. 56 hours
d. 15 hours
Answer  Explanation 

ANSWER: 56 hours

Explanation:
pipes and cisterns


4)   Raj swims 26 km downstream in same time as 14 km upstream. What is his speed in still water if speed of stream is 3 km/hr?

a. 10 km/hr
b. 12 km/hr
c. 7 km/hr
d. 4 km/hr
Answer  Explanation 

ANSWER: 10 km/hr

Explanation:
boats and streams


5)   If at same rate of interest, in 2 years, the simple interest is Rs. 40 and compound interest is Rs. 41, then what is the principal?

a. Rs. 500
b. Rs. 400
c. Rs. 800
d. Rs. 820
Answer  Explanation 

ANSWER: Rs. 400

Explanation:
compound interest


6)   P and Q start a cafe with a capital Rs. 20,000 and Rs. 40,000 respectively. After a year, out of the profit of Rs. 15000, P gets his share of profit plus some money as his salary. In total if P gets Rs. 7000, what is the salary amount he received?

a. Rs. 2000
b. Rs. 5000
c. Rs. 2500
d. Rs. 7500
Answer  Explanation 

ANSWER: Rs. 2000

Explanation:
partnership


7)   Two houses are in front of each other. Both have chimneys on their top. The line joining the chimneys makes an angle of 45° with the ground. How far are the houses from each other if one house is 25m and other is 10m in height?

a. 18 m
b. 12 m
c. 7.5 m
d. 15 m
Answer  Explanation 

ANSWER: 15 m

Explanation:
height and dstance


8)   Ajay has 2 cones with him. 1st cone has radius twice the other and height half the other. What is volume ratio of 1st and 2nd cones?

a. 2:1
b. 3:4
c. 1:2
d. 4:3
Answer  Explanation 

ANSWER: 1:2

Explanation:
volume and surface area


9)   When difference between compound and simple interest for three years is Rs. 122 at 5% rate per annum, the principal is ______

a. Rs. 24400
b. Rs. 14400
c. Rs. 18000
d. Rs. 16000
Answer  Explanation 

ANSWER: Rs. 16000

Explanation:
compound interest


10)   When payment is made online, discount offered is 10%. Additional discount of 5% is given to SBI credit card holders. Pratik buys a phone of Rs. 15000 by paying online and pays through his SBI credit card. How much does he need to pay?

a. Rs. 15000
b. Rs. 12825
c. Rs. 13500
d. Rs. 12750
Answer  Explanation 

ANSWER: Rs. 12825

Explanation:
discount


11)   In Cricket League, in first round every team plays a match with every other team. 9 teams participated in the Cricket league. How many matches were played in the first round?

a. 36
b. 72
c. 9!
d. 9! - 1
Answer  Explanation 

ANSWER: 36

Explanation:
permutation combination


12)   When two coins are tossed simultaneously, what are the chances of getting at least one tail?

a. 3/4
b. 1/5
c. 4/5
d. 1/4
Answer  Explanation 

ANSWER: 3/4

Explanation:
probability


13)   A cylinder having radius 1 m and height 5 m, is completely filled with wine. In how many conical flasks can this wine be filled into if the flask radius and height is 50 cm each?

a. 50
b. 500
c. 120
d. 160
Answer  Explanation 

ANSWER: 120

Explanation:
volume and surface area


14)   A started a travel agency using his Rs. 45000. B realized the profit in the business and joined after 3 months with his Rs. 60000. C came a bit late and after another 6 months invested Rs. 90000. Out of total profit of Rs. 20000 obtained after a year, what is share of C?

a. Rs. 5000
b. Rs. 4000
c. Rs. 9000
d. Rs. 9500
Answer  Explanation 

ANSWER: Rs. 4000

Explanation:
partnership


15)   What is value of 2(-2)2

a. 1/16
b. 1/8
c. 32
d. 16
Answer  Explanation 

ANSWER: 16

Explanation:
indices and surds


16)   The least common multiple of two numbers is 168 and highest common factor of them is 12. If the difference between the numbers is 60, what is the sum of the numbers?

a. 108
b. 96
c. 122
d. 144
Answer  Explanation 

ANSWER: 108

Explanation:
hcf lcm


17)   If a tank can be build by 18 men in 28 days while working for 9 hours per day, how many hours per day do 21 men have to work for 36 days, to complete the same tank?

a. 4
b. 5
c. 9
d. 6
Answer  Explanation 

ANSWER: 6

Explanation:
chain rule


18)   What is value of 22(-2)

a. -16
b. -42
c. 42
d. 1/16
Answer  Explanation 

ANSWER: 42

Explanation:
indices and surds


19)   Raj can build a house alone in 16 days but Suraj alone can build it in 12 days. Raj and Suraj work on alternate days. If Raj works on first day, the house will be built in how many days?

a. 12.5 days
b. 13(3/4) days
c. 48/7 days
d. 24/7 days
Answer  Explanation 

ANSWER: 13(3/4) days

Explanation:
time and work


20)   By what least number should we multiply 1008 to make it a perfect square?

a. 8
b. 7
c. 2
d. 5
Answer  Explanation 

ANSWER: 7

Explanation:
square root and cube root