Question

if a number is 20 less than other number. if there some is 90. find the number​

Answer 1

20/100 x 90 = 18

hence 18 is the correct answer

Answer 2

GIVEN:

The first number is 20 less than the second number.

Sum of both numbers is 90

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SOLUTION:

First off, let's assume the first number to be 'x' and the second number as 'y'.

According to the question, x = y - 20

==> x - y = -20 (Eqn 1)

Sum = 90, I.e, x + y = 90 (Eqn 2)

Now, since we've got a pair of linear equations, let's solve them!

Using Elimination Method, x - y = -20

x + y = 90

Add ==> 2x = 70

==> x = 35

Since, we have found x, by Eqn (2), we can find y as well;

I.e, x + y = 90

--> y = 90 - 35

--> y = 55

∴ The required numbers are 35 and 55