Question

Write a program to display all the number between 100 to 500 divisible by 15 as well as 20. please give answer​

Answer 1

Answer:

First let's find out the first number that is divisible by 7 in 100−500 .

15×7=105.

So, 105 is the first number.

Now, let's find the last number.

71×7=497 .

So, 497 is the last number.

The first number is 105 , let's assume that's our first number of a series(Arithmetic Series) and last is 497 . Common difference is 7 .

Now, nth term will be T(n)=105+(n−1)7

Here, solve for ′n′ by putting nth term as 497 .

497=105+(n−1)7

(n−1)7=497−105

(n−1)7=392

(n−1)=392/7

(n−1)=56

n=56+1

n=57

So, there are 57 terms in the series and hence there are 57 multiples of 7 in 100−500 .