Question

An urn contains 10 tickets numbered 1 to 10. 4 tickets are

drawn one by one with replacement. Then the probability that

largest number drawn is not more than 7 and smallest is not less than 2.

• A.
• B.
• C.
• D.

Answer 1

Answer: (A)

Answer 2

1(2,3,4,5,6,7)8,9,10

P(5) = $\frac { { } ^ { 6 } \mathrm { C } _ { 2 } } { { } ^ { 10 } \mathrm { C } _ { 4 } }$.