Question

Jenny says "If you subtract 13 from my number and multiply the difference by -7, the result is -56." What is Jenny's number?

A. 21.
B. 56.
C. 69.
D. 104.

Answer 1

Jenny's number is found by solving the equation (Jenny's number - 13) × -7 = -56. After dividing by -7 and adding 13, Jenny's number is determined to be 21.

Step-by-step explanation:

The student needs to solve for Jenny's number based on the condition given that when 13 is subtracted from her number and the difference is multiplied by -7, the result is -56. To find Jenny's number, we start by setting up an equation based on the condition:

(Jenny's number - 13) × -7 = -56

Now let's solve for Jenny's number step-by-step:

1. First, divide both sides of the equation by -7 to isolate the term with Jenny's number:
   Jenny's number - 13 = -56 / -7
2. Calculate the division on the right side of the equation:
   Jenny's number - 13 = 8
3. Finally, add 13 to both sides of the equation to solve for Jenny's number:
   Jenny's number = 8 + 13
4. Now we can say that Jenny's number is 21.

Therefore, option A. 21 is the correct answer.