
can you help to solve this problem please?
can you help to solve this problem please?
25 × $0.20 = $5
$5 ÷ $0.50 = 10
This means that 25 20¢ coins were exchanged for 10 50¢ coins.
20¢ coins | 50¢ coins |
|
Before | 1 unit | 2 units |
Change | -25 | +10 |
After | 1 part | 8 parts |
Making the 20¢ column into 8 parts:
20¢ coins | 50¢ coins |
|
Before | 8 units | 2 units |
Change | -200 | +10 |
After | 8 parts | 8 parts |
8 units – 200 = 2 units +10
8 units – 2 units = 10 + 200
6 units = 210
1 unit = 210 ÷ 6
= 35 (no. of 20¢ coins)
2 units = 35 × 2
= 70 (no. of 50¢ coins)
35 × $0.20 = $7
70 × $0.50 = $35
$35 + $7 = $42