The ratio of the volumes of two cubes is 729 : 1331. What is the ratio of their total surface areas?
A. 81 : 121
B. 9 : 11
C. 729 : 1331
D. 27 : 12
Ratio of the sides = ³√729 : ³√1331 = 9 : 11
Ratio of surface areas = 92 : 112 = 81 : 121
A. 81 : 121
B. 9 : 11
C. 729 : 1331
D. 27 : 12
Ratio of the sides = ³√729 : ³√1331 = 9 : 11
Ratio of surface areas = 92 : 112 = 81 : 121
A. 32%
B. 42%
C. 52%
D. 62%
Explanation:
Total = 100
T= 40 NT= 60
40*(60/100)=24 60*(40/100)=24
24 + 24 = 48 => 100 – 48 = 52%
A. 6 days
B. 8 days
C. 10 days
D. 12 days
2 children = 1 man
(8 children + 12 men ) = 16 men
Now, less men, more days
12 : 16 : 9 : x
x = 16×9/12=12 days
A. 4 : 3
B. 8 : 7
C. 4 : 1
D. 6 : 5
Let the length and breadth of the carpet in the first case be 3x units and 2x units respectively.
Let the dimensions of the carpet in the second case be 7y, 3y units respectively.
From the data,.
2(3x + 2x) = 2(7y + 3y)
=> 5x = 10y
=> x = 2y
Required ratio of the areas of the carpet in both the cases
= 3x * 2x : 7y : 3y
= 6×2 : 21y2
= 6 * (2y)2 : 21y2
= 6 * 4y2 : 21y2
= 8 : 7
A. 55/601
B. 601/55
C. 11/120
D. 120/11
Explanation:
Let the numbers be a and b.
Then, a + b = 55 and ab = 5 * 120 = 600.
Required sum = 1/a + 1/b = (a + b)/ab = 55/600 = 11/120.
A. 24 cm,48cm
B. 12cm,24cm
C. 6√2cm,12√2cm
D. 6cm,12cm
A. Rs. 1620
B. Rs. 1640
C. Rs. 1680
D. Rs. 1700
Explanation:
Principal = (P.W. of Rs. 882 due 1 year hence) + (P.W. of Rs. 882 due 2 years hence)
= [882/(1 + 5/100) + 882/(1 + 5/100)2]
= (882 * 20)/21 + (882 * 400)/441 = Rs. 1640.