SOLUTION: The sum of 3 numbers is 15. The second number is double the first. The third number is 5 less than the first. What are the three numbers?

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Question 754761: The sum of 3 numbers is 15. The second number is double the first. The third number
is 5 less than the first. What are the three numbers?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Write an equation for each statement
:
The sum of 3 numbers is 15.
a + b + c = 15
The second number is double the first.
b = 2a
:
The third number is 5 less than the first.
c = (a-5)
;
What are the three numbers?
:
In the 1st equation, replace b with 2a, replace c with (a-5)
a + 2a + (a-5) = 15
4a = 15 + 5
a = 20/4
a = 5
Find b
b = 2(5)
b = 10
find c
c = 5 - 5
c = 0
:
Check: 5 + 10 + 0 = 15