The sum of two numbers is 21 .two-thirds of one number is added to three-quarters of the other number to give 15 .find the two numbers,showing clearly your workings.

simple translation from English to Math (after all Math is just a language)

let 1st number be x
let 2nd number be y

x + y = 21

(2/3)x + (3/4)y = 15
multiply each term by 12
8x + 9y = 180

I would use substitution,
from the 1st equation ----> y = 21-x
sub that into the 2nd

go for it, just a few more steps

more explanation should be given

Substitution method

Wrong equation

The sim of two numbers is 21.3/4 of one of the number added to 2/3 of the other gives a sum of 15.find The two number

I have not my answer

Substitution wrong

Maths

More explanation

6 years ago