Oliver bought a total of 15 sweets and mochi balls. Each sweet cost 40¢. Each mochi ball cost 50¢. He paid a total of $6.80. How many mochi balls did he buy?
Number of
sweets |
Amount paid
for the sweets |
Number of
mochi balls |
Amount paid
for the sweets |
Total paid |
| 15 |
15 x 40
= 600¢ |
0 |
0 |
600¢ |
| 14 |
14 x 40
= 560¢ |
1 |
1 x 50
= 50¢ |
610¢ |
| 7 |
7 x 40
= 280¢ |
8 |
8 x 50
= 400¢ |
680¢ |
$1 = 100¢
$6.80 = 680¢
Amount paid if all were sweets
= 15 x 40
= 600¢
Big difference between the amount paid for the sweets and the mochi balls
= 680 - 600
= 80¢
Small difference between the amount paid for the one sweet and one mochi ball
= 50 - 40
= 10¢
Number of mochi balls
= 80 ÷ 10
= 8
Answer(s): 8
