q: A and B can do a work in 10 days and 15 days respectively. A starts the work and B joins him after 3 days. In how many days can they complete the remaining work?
Options:
(A) 6 days
(B) 2 days
(C) 8 days
(D) 4 1/5 days
(E) 9 days
a: Work done by A in 3 days = 3/10
Remaining work = 7/10
Work done by both A and B in one day = 1/10 + 1/15 = 5/30 = 1/6
Remaining work = 7/10 * 6/1 = 21/5 = 4 1/5 days. The answer is (D).
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q: If rupee one produces rupees nine over a period of 54 years, find the rate of simple interest?
Options:
(A) 22 1/7 %
(B) 22 3/2 %
(C) 22 1/8 %
(D) 22 1/2 %
(E) 16 2/3 %
a: 9 = (1*54*R)/100
R = 16 2/3 % The answer is (E).
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q: A password for a computer is six digits from 0 and 9. The six digit number is a prime number. What is the approximate probability that the last digit is a 3?
Options:
(A) 1/4
(B) 1/6
(C) 1/10
(D) 1/20
(E) 1/50
a: If the last digit is 0, 2, 4, 6, or 8, the number is even and therefore not prime. If the last digit is 5, the number is divisible by 5 and therefore not prime. The only possibilities are 1, 3, 7, and 9. So the probability is approximately 1/4 (answer A). We say approximately because there is a certain degree of randomness in the distribution of prime numbers. The answer is (A).
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q: A no. when divided by the sum of 555 and 445 gives 2times their difference as quotient & 70 as remainder. Find the no. is?
Options:
(A) 145646
(B) 236578
(C) 645353
(D) 456546
(E) 220070
a:
(555 + 445) * 2 * 110 + 70 = 220000 + 70 = 220070 The answer is (E).
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