Question

In pack of ten books, three are geometry books while the rest are book on algebra. If three books are drawn at random, what is the probability that one of them is geometry book and the others are book on algebra​

Answer 1

Answer:

21/40.

Step-by-step explanation:

There are 3 geometry and 7 algebra books.

If the geometry book is drawn first probability = 3/10

If the second is algebra P = 7/9.

If the third is algebra P = 6/8 = 3/4.

So the probability  of all three being drawn in this order = 3/10 * 7/9 * 3/4

= 63/360

= 7/40.

Now there are a total of 3 ways in the order they are drawn, That is:

GAA

AGA

AAG.

So the required probability = 3 * 7/40

= 21/40.