Andy has 16 notes. There are only ten-dollar notes and one hundred-dollar notes. The total amount of money is $520. How many one hundred-dollar notes does Andy have?
Number of
one hundred-dollar notes |
Value of
one hundred-dollar notes |
Number of
ten-dollar notes |
Value of
ten-dollar notes |
Total
value |
| 16 |
16 x 100 = $1600 |
0 |
0 |
$1600 |
| 15 |
15 x 100 = $1500 |
1 |
1 x 10
= $10 |
$1510 |
| 4 |
4 x 100 =
$400 |
12 |
12 x 10 = $120 |
$520 |
Total amount of money if all the notes are one hundred-dollar notes
= 16 x 100
= $1600
Big difference between the amounts of one hundred-dollar notes and ten-dollar notes
= 1600 - 520
= $1080
Small difference between amount in one one hundred-dollar note and one ten-dollar note
= 100 - 10
= 90
Number of ten-dollar notes
= 1080 ÷ 90
= 12
Number of one hundred-dollar notes
= 16 - 12
= 4
Answer(s): 4
