SOLUTION: The sum of 3 numbers is 42. The second number is 2 more than twice the first number and the third number is 3 less than the second number. Find the 3 numbers.

Algebra.Com
Question 268260: The sum of 3 numbers is 42. The second number is 2 more than twice the first number and the third number is 3 less than the second number. Find the 3 numbers.
Answer by ankor@dixie-net.com(22740)   (Show Source): You can put this solution on YOUR website!
Three numbers: a, b, c
:
Write an equation for each sentence.
:
The sum of 3 numbers is 42.
a + b + c = 42
:
The second number is 2 more than twice the first number
b = 2a + 2
:
the third number is 3 less than the second number.
c = b - 3
from the 2nd equation, replace b with (2a+2)
c = (2a + 2) - 3
c = 2a - 1
:
Find the 3 numbers.
:
a + b + c = 42
Substitute for b and c
a + (2a+2) + (2a-1) = 42
5a + 1 = 42
5a = 42 - 1
5a = 41
a =
a = 8.2 is the 1st number
then
b = 2(8.2) + 2
b = 16.4 + 2
b = 18.4
and
c = 2(8.2) - 1
c = 16.4 - 1
c = 15.4
:
Check:
8.2 + 18.4 + 15.4 = 42

RELATED QUESTIONS

the sum of 3 numbers is 123. the second number iis 2 more than twice the first number.... (answered by stanbon)
The sum of three whole numbers is 7. The second number is 1 more than the twice of the... (answered by ewatrrr)
The sum of three numbers is 26 if the second number is 3 more than four times the first... (answered by macston)
The sum of 3 integers is 123. The second number is two more than twice the first number.... (answered by mananth,josmiceli)
The sum of 3 numbers is 38. The second number is 9 more than double the first, and the... (answered by lynnlo)
In a set of numbers, the second number is 3 more than twice the first, and the third... (answered by ikleyn)
1. The fifth number plus the third number equals 2. The fourht number is one more than... (answered by mananth)
The sum of three numbers is 105. The third number is 11 less than 10 times the second... (answered by lwsshak3)
The sum of 3 numbers is 34. The first number is 3 less than the second and the third is 4 (answered by scott8148)