Q.
The number of numbers, lying between 99 and 1000 that can be made from the digits 2,3,7,0,8 and 6 when the digits occur only once in each number, is
Required number of numbers =6P3−5P2=120−20=100 .
{Since, between 99&1000 , the numbers are of 3 digits, but those numbers should be omitted in which 0 comes at hundreds place}.