Selena was charged $24 x 2 = $<<24*2=48>>48 for the steaks.
She was charged $3.5 x 2 = $<<3.5*2=7>>7 for the burgers.
She was charged $2 x 3 = $<<2*3=6>>6 for the cups of ice cream.
She was charged $48 + $7 + $6 = $<<48+7+6=61>>61 in total.
Therefore, Selena was left with $99 - $61 = $<<99-61=38>>38.
#### 38