Question

How many two digit numbers are thhere which are divisible by 5?

Answer 1

A.p is 10,15,20...95

an=a+(n-1)d

95=10+(n-1)5

95-10/5=n-1

85/5=n-1

17=n-1

17+1=n

18=n

so,18 two digit no. are there which are divisible by 5