please solve the fourth word problem

[barbie]

The sum of three numbers is
105
. The first number is
5
less than the second. The third number is
3
times the second. What are the numbers?

 

[math_celebrity]

Let x be the first number, y be the second number, and z be the number. We have the following equations:

1. x + y + z = 305
2. x = y - 5
3. z = 3y

Substitute (2) and (3) into (1)
(y - 5) + y + (3y) = 305

Combine like terms:
5y - 5 = 305

Use our equation solver
y = 62

Substitute y = 62 into (3)
z = 3(62)
z = 186

x = (62) - 5
x = 57