Question
There are 30 cars standing in a parking lot which
consist of silver, grey and white cars. The number of grey and white cars are equal, and the number of silver cars is 3 more than the number of white cars. If 3 cars are randomly selected, what is the probability that at least one of them is silver?Solution
Let the number of grey and white cars be ’x’ each. Then the number of silver cars will be ‘x + 3’. So, (x + 3) + x + x = 30 3x = 27 x = 9 So, number of silver, grey and white cars is 12, 9 and 9 respectively. Required probability = P (at least one of them is silver) = 1 – P (none of them is silver) = 1 – (18/30) × (17/29) × (16/28) = 1 – (204/1595) = (1391/1595)
More Probability Questions
- Select the number from among the given options that can replace the question mark (?) in the following series.
17, 18, 22, 31, 47, ___ - Select the number that can replace the question mark (?) in the following series.
24, 28, 37, 53, 78, ? - Which letter-cluster will replace the question mark (?) in the following series?
RGV, UME, ?, AYW, DEF - Which letter and number cluster will replace the question mark (?) to complete the given series?
LT6, KU12, IW24, FZ48, ____ - A series is given with one term missing. Choose the correct alternatives from the given ones that will complete the series.
57, 59, 56, 61, 54, ___ - Select the letter-pair that can replace the question mark (?) in the following series?
FK, HM, LQ, RW, ZE, ? - Which letter-cluster will replace the question mark (?) in the following series?
NPQR, OORQ, PNSP, ____, RLUN