he population of a city is 140,000. If it increases at the rate of 6% per annum, then what will be its population 2 years hence?
Options:
(A) 1797787
(B) 1597723
(C) 159776
(D) 159728
(E) 157304
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Population after n years = P [1 + (R/100)]2
Population after 2 years = 140000 * [1 + 6/100]2 = (160000 x 53/50 x 53/50) = 157304 So the answer is: (E).
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Find the number of zeroes in the expression 15*32*25*22*40*75*98*112*125
Options:
(A) 9
(B) 8
(C) 7
(D) 6
(E) 5
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Maximum power of 5 in the above expression can be calculated like this. Count all the powers of 5 in the above expression. So number of zeroes are 9. So the answer is: (A).
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Before lunch, a painter can paint a wall at a rate of r square feet per minute. The same painter, after lunch and a cup of coffee, can paint the same wall at a rate r + 1 square feet per minute, and the same wall would be finished in 30 seconds less time. What is the value of r?
Options:
(A) 1/3
(B) 3
(C) 1/2
(D) 1
(E) 2
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Convert 30 seconds to 1/2 minute
Equation: 1/r = 1/(r + 1) + 1/2
Plug options into the equation:
D fits: 1/1 = 1/(1 + 1) + 1/2 So the answer is: (D).
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