One number is 8 times a first number. A third number is 100 more than the first number. If the sum of the three numbers is 420?, find the numbers.

Question

what are the three numbers in the equation

Answer 1

here's what we know:

a + b + c = 420 (The sum of the three numbers is 420)

b = 8a (the second number is 8 times the first number)

c = a + 100 (the third number is 100 more than the first)

 

Let's plug the variables in:

a + 8a + a + 100 = 420

combine like terms:

10a + 100 = 420

Subtract 100:

10a = 320

Divide by 10:

a = 32

 

b = 32 * 8

b = 256

 

c = 32 + 100

c = 132

 

check:

32 + 256 + 132 = 420

420 = 420