Answer: the amount of money that Deandra has is $15
Step-by-step explanation:
Let f represent the amount of money Frank has in dollars.
let d represent the amount of money Deandra has in dollar.
Frank has three times as many dollars as Deandra. This means that
f = 3d
Charlie has 20 more dollars than Frank. If Charlie has $65, it means that the amount that Frank has is
65 - 20 = $45
Substituting f = 45 into f = 3d, it becomes
45 = 3d
d = 45/3
d = 15