Carcass wrote:
Chelsea has 5 roses and 2 jasmines. A bouquet of 3 flowers is to be formed. In how many ways can it be formed if at least one jasmine must be in the bouquet?
(A) 5
(B) 20
(C) 25
(D) 35
(E) 40
Here,
Let us consider the possibilities::
CASE I 1 rose and 2 jasmines which can be arranged in = 5C1 * 2C2 = 20
CASE II2 roses and 1 jasmines which can be arranged in = 5C2 * 2C1 = 5
Therefore the total no. of possibilities = 20 + 5 = 25
I think you got the calculations mixed up. 5C2 * 2C1 = 20 etc.