Question

the sum of two numbers is 90 and the greator number exceeds twice the smaller by 15.Find the numbers

Answer 1

Let the greater no. be x and the smaller no. be y.

Since there are two variables, we will need two equations which can further be solved by your method of convinence ( Elimination/ Substitution or Cross multiplication)

ATQ,

x+ y= 90 --------- (1)

x- 2y= 15-------- (2)

By using substitution, we get x= 90-y and substituting it in eq. 2

90 - y - 2y = 15

90 -3y = 15

-3y = 15 - 90

-3y = - 75

y= 75/ 3

y= 25

So, the smaller no. is 25 and the greater no. will be x= 90 - 25 = 65

Answer 2

Given that the sum of two numbers is 90.

Let the smaller number x.

Then the larger number will be (90 - x).

Given that greater number exceeds twice the smaller by 15.

(90 - x) = 2x + 15.

90 - x = 2x + 15

90 = 3x + 15

3x = 75

x = 25.

If the smaller number is 25 then the larger number will be 90 - x = 90 - 25 = 65

The numbers are 25 and 65.