Question

How many whole numbers between 99 and 999 contain exactly one 0

Answer 1

to find no. with exactly 1 0

we have to find the number of multiple of 10..

so , a = 110
d = 10
an = 990

so,. 990 = 110+ (n-1)10
n = 89

but the number given above also includes numbers with double zero such as 100 200-300 etc. .
so we have to subtract the no. of multiple of 10 with double zero..

so, multiple of 10 with double zero between 99 and 999 are--
100,200,300,400,500,600,700,800,900

there are total 9 multiples of 10 with double zero so we subtract 9 from 89.

so, the number of whole numbers between 99 and 999 with exactly one 0 is 80..

HOPE it helps you..

Answer 2

Answer:

80

Step-by-step explanation:

What the other one said.