There were a total of thirty-five 10-cent coins and 20-cent coins in a bag. Given that the total amount of money in the bag was $5.40. How many 10-cent coins were there in the bag?
Number of 20-cent coins |
Value of 20-cent coins |
Number of 10-cent coins |
Value of 10-cent coins |
Total value |
35
|
35 x 20 = 700¢ |
0
|
0
|
700¢
|
34
|
34 x 20 = 680¢ |
1
|
1 x 10 = 10¢ |
690¢
|
19
|
19 x 20 = 380¢ |
16
|
16 x 10 = 160¢ |
540¢ |
$1 = 100¢
$5.40 = 540¢
Amount in the bag if all are 20-cent coins
= 35 x 20
= 700¢
Big difference between the value of 20-cent coins and 10-cent coins
= 700 - 540
= 160¢
Small difference between the value of one 20-cent coin and one 10-cent coin
= 20 - 10
= 10¢
Number of 10-cent coins
= 160 ÷ 10
= 16
Answer(s): 16