Sir please give me a detailed solution of this question in which we have to find the numbers between 101 and 999 which are completely divisible by both 2 and 5.
RS Aggarwal, class 10, chapter 5A, question no 45.
Rajan@2021Guru
How many numbers are there between 101 and 999, which are divisible by both 2 and 5?
Share
The list of numbers between 101 and 999 that are divisible by 2 and 5 are:
110,120,130,...990
The numbers are in A.P, with first term, a=110, common difference, d=10
Last term, an=990
We know that, an=a+(n−1)d
990=110+(n−1)10
⇒990–110=10n–10
⇒880+10=10n
⇒890=10n
⇒n=89
Therefore, the number of terms between 101 and 999 that are divisible by 2 and 5 are 89.