Problem
Joan has a gym gift card worth $\$ 100$. Each time she visits the gym, $\$ 12$ is deducted from the amount remaining on the gift card. Which equation can be used to determine the amount of money $(m)$, in dollars, remaining on the gift card after Joan visits the gym $d$ times? A. $m=12-100 d$ B. $m=12 d-100$ C. $m=-12+100 d$ D. $m=-12 d+100$
Solution
Step 1 ：Joan has a gym gift card worth \($100\). Each time she visits the gym, \($12\) is deducted from the amount remaining on the gift card. We need to find the equation that represents the amount of money remaining on the gift card after Joan visits the gym d times.
Step 2 ：The correct equation is \(m = -12d + 100\).
