Question

Mika’s gym allows her to bring 3 guests for free. After the first three, she must pay $7 per guest. How many guests, g, can she bring to the gym if she pays $42? Three of these equations give the correct value of g. Which equation does NOT? A 7g = 63

B 7(g – 3) = 42
C 7g – 3 = 42
D g = 9
all help is appreciated

Answer 1

C) 7g - 3=42
All the other ones give the correct value of g except 7g-3=42 because the value of g is 9.

Answer 2

C. 7g – 3 = 42

Explanation:

If she pays $7 for each guest and totally paid 42$. Then, she can bring 42/7 = 6 guests with payment. She can also bring 3 guests for free. In total, she can bring 6+3 = 9, g must be 9. When you look at the choices, all the others satisfy this except C 7g – 3 = 42.