Tommy sells skirts and cardigans. For each skirt he sells, he earns $39. For each cardigan he sells, he earns $20. In January, he sold 31 skirts and cardigans altogether and earned $791. How many skirts did he sell?
Number of
skirts |
Amount earned
from the skirts |
Number of
cardigans |
Amount earned
from the cardigans |
Total amount
earned |
31
|
31 x 39
= $1209 |
0
|
0
|
$1209
|
30
|
30 x 39
= $1170 |
1
|
1 x 20 =
$20 |
$1190 |
| 9 |
9 x 39
= $351 |
22
|
22 x 20 =
$440 |
$791
|
Amount that Tommy earns if he sells 31 skirts
= 31 x 39
= $1209
Big difference between the amount on the skirts and the cardigans
= 1209 - 791
= $418
Small difference the amount on one skirt and the cardigan
= 39 - 20
= $19
Number of cardigans that Tommy sold in January
= 418 ÷ 19
= 22
Number of skirts that Tommy sold in January
= 31 - 22
= 9
Answer(s): 9
