someone explain this question for me plssssss

Question

Sasha has a number of bills in his wallet totaling $50. If his wallet has at least 1 single, 1 five-dollar bill, 1 ten-dollar bill, and 1 twenty-dollar bill, then what is the range of possible bills he can have in his wallet?

1. 
   

Answer 1

If his wallet has at least 1 single, 1 five-dollar bill, 1 ten-dollar bill, and 1 twenty-dollar bill....

That's a total of 4 bills (MINIMUM) with a combined value of $36.

To solve something like this, I think you have to list all the possible combinations.

NOTE: they say "at least" one single, but this is not applied to the fives, tens, or the twenty.

I think you simply have to list all the possible combinations that add up to $50

Answer 2

Take away the $1, $5, $10 and $20 bills from the $50 you have $14 left.

$14 can be 14 $1 total 15 $1, 1 $5, 1 $10 and 1 $20

4 $1 and 1 $10 or total 5 $1, 1 $5, 2 $10 and 1 $20

4 $1 and 2 $5. total 5 $1, 3 $5, 1 $10 and 1 $20

so number of $1 is either 5 or 15

number of $5 is either 1 or 3

number of $10 is either 1 or 2

number of $ 20 is 1