Answer:
A) 400 + 72
Explanation:
Let the certain number be denoted by x.
⇒ 5x = 40 [Equation 1]
⇒ 9x = 72 [Equation 2]
Multiply Equation 1 by 10 :
⇒ 10(5x) = 40(10)
⇒ 50x = 400 [Equation 3]
Finding the sum of Equation 2 and Equation 3 :
⇒ 50x + 9x = 400 + 72
⇒ 59x = 400 + 72
Hence, 59 times a certain number is represented by : 400 + 72