The sum 24

The sum of the three numbers is 80. The first number is 8 less than the third. The second number is 2 times the third. What are the numbers?

Final Answer:

a =  14
b =  44
c =  22

Step-by-step explanation:

$$\begin{gathered} a+b+c=80 \\ a=c-8 \\ b=2\cdot c \\ a+b+c=80 \\ a-c=-8 \\ b-2c=0 \\ Row2-Row1\to Row2 \\ -b-2c=-88 \\ Row3+Row2\to Row3 \\ -4c=-88 \\ c=\frac{-88}{-4}=22 \\ b=\frac{-88+2c}{-1}=\frac{-88+2\cdot 22}{-1}=44 \\ a=80-b-c=80-44-22=14 \\ a=14 \\ b=44 \\ c=22 \end{gathered}$$

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