Directions: Each of the questions given below is followed by series of options among which you have to choose the best one. You can also review your choices by clicking into answer section.
16. In a college, the ratio of the number of boys to girls is 8 : 5. If there are 160 girls, find the total number of students in the college.
A. 100
B. 260
C. 250
D. 416
Answer
Explanation:
Let the number of boys and girls be 8x and 5x.
Total number of students = 13x = 13 x 32 = 416.
17. Find the mean proportion between 5 and 45.
A. 9
B. 15
C. 25
D. 50
Answer
Explanation:
5:x::x:45
x²=45*5 = 225 x=15
18. Rs. 730 were divided among A, B, C in such a way that if A gets Rs. 3, then B gets Rs. 4 and if B gets Rs. 3.50 then C gets Rs.3. The share of B exceeds that of C by:
A. Rs.30
B. Rs.70
C. Rs.40
D. Rs.210
Answer
Explanation:
A:B = 3:4 and B:C = (7/2):3 = (8/7)*(7/2)*(8/7)*3 = 4:(24/7)
A: B : C = 3 :4: 24/7 = 21 : 28 : 24.
B’s share = Rs.[730 *(28/73)]= Rs.280.
C’s share = Rs.[730 * (24/73)] = Rs.240.
Difference of their shares = 40
19. The sum of squares of three numbers is 280. If the numbers are in the ratio 3:5:6, find the greatest number.
A. 8
B. 6
C. 12
D. 18
Answer
Explanation:
Let the numbers be 3x, 5x and 6x.
(3x)²+(5x)²+(6x)²=280
9x²+25x²+36x²=280
70x²=280
x²=4
x=2
Hence, The greatest number is 6x=12.
20. The least whole number which when subtracted from both the terms of the ratio 6 : 7 to give a ratio less than 16 : 21, is.
A. 2
B. 4
C. 3
D. 6
Answer
Explanation:
Let x is subtracted.
Then, ((6 – x)/(7 – x)) < 16 / 21
21(6—x) < 16(7—x)
⇒ 5x > 14
⇒ x > 2.8.
Least such number is 3.
21. X, Y and Z are quantities of the same kind such that X:Y=5:8 and Y:Z=4:7. Find X:Z.
A. 32:35
B. 67:56
C. 5:14
D. 5:7
Answer
Explanation:
X:Z=(X:Y)*(Y:Z)
=(5:8)*(4:7)
= (5/8)*(4/7)
= 5/14
22. If 0.4 : 1.4 :: 1.4 : x, the value of x is ?
A. 49
B. 0.49
C. 4.9
D. 0.4
Answer
Explanation:
0.4 * x = 1.4 * 1.4
or, x = (1.4*1.4)/0.4
Hence, x = 4.9
23. Pooja, Amanda and Sherin divide 93 chocolates between them in the ratio (1/2):(1/3):(1/5). How many chocolates did Amanda get?
A. 31
B. 30
C. 21
D. 45
Answer
Explanation:
(1/2):(1/3):(1/5) = (15/30):(10/30):(6/30) = 15:10:6
Amanda's share = [10/(15+10+6)]*93 = [10/31]*93 = 30
24. The compounded ratio of (2 : 3), (6: 11) and (11 :2) is ?
A. 1: 2
B. 11: 24
C. 2: 1
D. 36: 121
Answer
Explanation:
Required ratio = (2/3) * () * (6/11) * (11/2) = 2/1
25. A bag contains 50 paisa, 1 rupee and 2 rupee coins in the ratio 2:5:8. If the total amount is Rs.352, find the total number of coins in the bag.
A. 160
B. 200
C. 250
D. 240
Answer
Explanation:
Let the number of 50p, 1 rupee and 2 rupee coins be 2x,5x & 8x.
or, 0.5*(2x) + 5x + 2*8x = 352
or, 22x = 352
So, x = 16
Total no. of coins = 2x+5x+8x = 15x = 240
