A fill pipe can fill a tank in 20 hours, a drain pipe can drain a tank in 30 hours. If a system of n pipes (fill pipes and drain pipes put together) can fill the tank in exactly 5 hours, which of the following are possible values of n (More than one option could be correct)? ...

The ratio between the height and radius of the base of a cylinder is 7 : 5. If its volume is 14836.5 cm3, then find its total surface area. a) 3010.5 b) 3391.2 c) 3232.3 d) 3555.4 Sol: Let the height be 7x and radius be 5x  According to the question,  Volume = π (5x)2 × 7x  ⇒ 14836.5 = ...

In the given figure, CD is angle bisector and AD = AM then find    = ? , if ∠ABC = 47°. a) 53° b) 143° c) 47° d) None of these Sol:

In the fig. CD = DE, BC = 4 cm, AE = 3 cm, ∠A = 90°. ABCD is a quadrilateral and EFGB is a square. Find the area of the square EFGB? a)            4 cm² b)            16 cm² ...

Find the number of zeroes at the end of the product 2 × 4 × 6 × 8 × 10 … × 180 a) 1 b) 0 c) 21 d) 120 Sol: 2 × 4 × 6 × 8 × 10 … × 180  ⇒ 290(1 × 2 × 3 × 4 × 5 × … × 90)  ⇒ 290 × 90!  In this case, number of 5’s is less than the number of 2’s. So we need to calculate the number of 5’s    ...

If the 6-digit numbers x35624 and 1257y4 are divisible by 11 and 72, respectively, then what is the value of (5x-2y)?  (a) 14 (b) 12 (c) 10 (d) 13 Sol: In such questions directly check divisibility by 11, 9 and 8. For a number to be divisible by 11, the difference of the ...

The price of tea increases by 32%, therefore the expenditure on tea increase by 10%. If 10 kg tea was bought earlier, then what is the quantity can buy now? a) 12 kg b) 8 1/3kg c) 6 2/3kg d) 9kg Sol: Let original price of the tea is and consumption after increase in price is y ...

What should replace * in the number 94*2357, so that the number is divisible by 11?  (a) 3 (b) 7 (c) 1  (d) 8 Sol: For a number to be divisible by 11, the difference of sum of alternative numbers is divisible by 11. Hence, (7+3+*+9)-(5+2+4) =(19+*)-(11) =8+* ...

If the nine-digit number 708x6y8z9 is divisible by 99, then what is the value of x+y+z?  (a) 9 (b) 16 (c) 5  (d) 27 Sol: It is given that 708x6y8z9 is divisible by 99. Thus, 708x6y8z9 is divisible by both 11 and 9 For divisibility by 9, sum of digits is divisible ...

A man borrowed Rs.50,000 from a bank at 10% per annum, compounded annually. At the end of every year, he pays Rs.15,000 as part payment of the loan and interest. How much does he still owe to the bank after three such instalments? a) 17200 b) 16900 c) 15500 d) 14300 Sol: ...