Bryan has 5-cent coins and 10-cent coins. The total value of all his coins is $26. He has 20 less 5-cent coins than 10-cent coins. How many coins does he have altogether?
| |
5-cent |
10-cent |
Total |
| Number |
1 u |
1 u + 20 |
2 u + 20 |
| Value |
5 |
10 |
|
| Total value |
5 u |
10 u + 200 |
15 u + 200 |
$1 = 100¢
$26 = 26 x 100 = 2600¢
Bryan has 20 more 10-cent coins than 5-cent coins.
Number of 5-cent coins = 1 u
Number of 10-cent coins = 1 u + 20
Total value of 5-cent coins
= 5 x 1 u
= 5 u
Total value of 10-cent coins
= 10 x (1 u + 20)
= 10 u + 200
Total value of the coins
= 5 u + 10 u + 200
= 15 u + 200
15 u + 200 = 2600
15 u = 2600 - 200
15 u = 2400
1 u = 2400 ÷ 15 = 160
Total number of coins
= 1 u + (1 u + 20)
= 2 u + 20
= 2 x 160 + 20
= 320 + 20
= 340
Answer(s): 340
