Question

The sum of three numbers is 73. The second number is equal to the first number diminished by 7. The third number is five times the first. What are the numbers? Which three expressions could be used to represent the number?
A. N; n-7; 5n
B. N+7; n-7;n
C.n+5; n-7;n

Answer 1

Answer:

A. n; n - 7, 5n

Step-by-step explanation:

$n\to first\ number\\n-7\to secon\ number\\5n\to third\ number\\73\to the\ sum\ of\ numbers\\\\\text{The equation:}\\\\n+(n-7)+(5n)=73\qquad\text{combine like terms}\\\\(n+n+5n)-7=73\qquad\text{add 7 to both sides}\\\\7n=80\qquad\text{divide both sides by 7}\\\\n=\dfrac{80}{7}\\\\n=11\dfrac{3}{7}\\\\n-7=11\dfrac{3}{7}-7=4\dfrac{3}{7}\\\\5n=5\cdot\dfrac{80}{7}=\dfrac{400}{7}=57\dfrac{1}{7}$