Question

The sum of three numbers is 120 the first number is five less than the second the third number is three times the second what are the numbers

Answer 1

1st number: 20

2nd number: 25

3rd number: 75

Explanation:

x + y + z = 120

x = y - 5

z = 3y

plug that in!

(y-5) + y + (3y) = 120

remove the parenthesis (I used them to show you what I was replacing), and add like terms.

5y - 5 = 120

move -5 to the other side

5y = 120 + 5

5y = 125

divide both sides by 5

y = 25

now that you have one number, use the equations from before to solve for the rest!

x = (25) - 5

z = 3(25)

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x = 20

y = 25

z = 75