PSLE Seven pupils shared the cost of a gift equally. When calculating the amount for each share, one of the pupils made a mistake by dividing the cost of the gift by 8 instead of 7. Each pupil paid $1.80 less than his share. What should be the cost of the gift?
|
8 pupils |
7 pupils |
Number |
8 |
7 |
Value |
1 u |
1 u + 1.80 |
Total value |
8 u |
7 u + 12.60 |
Cost of the gift if shared by 8 pupils
= 8 x 1 u
= 8 u
Cost of the gift if shared by 7 pupils
= 7 x (1 u + 1.80)
= 7 u + 12.60
The total amount that the 8 pupils shared is the same as the total amount that the 7 pupils shared.
8 u = 7 u + 12.60
8 u - 7 u = 12.60
1 u = 12.60
Cost of the gift
= 8 u
= 8 x 12.60
= $100.80
Answer(s): $100.80