Oscar bought a total of 11 mochi balls and sweets. Each mochi ball cost 40¢. Each sweet cost 90¢. He paid a total of $6.40. How many sweets did he buy?
Number of
mochi balls |
Amount paid
for the mochi balls |
Number of
sweets |
Amount paid
for the mochi balls |
Total paid |
| 11 |
11 x 40
= 440¢ |
0 |
0 |
440¢ |
| 10 |
10 x 40
= 400¢ |
1 |
1 x 90
= 90¢ |
490¢ |
| 7 |
7 x 40
= 280¢ |
4 |
4 x 90
= 360¢ |
640¢ |
$1 = 100¢
$6.40 = 640¢
Amount paid if all were mochi balls
= 11 x 40
= 440¢
Big difference between the amount paid for the mochi balls and the sweets
= 640 - 440
= 200¢
Small difference between the amount paid for the one mochi ball and one sweet
= 90 - 40
= 50¢
Number of sweets
= 200 ÷ 50
= 4
Answer(s): 4
