PSLE Six pupils shared the cost of a present equally. When calculating the amount for each share, one of the pupils made a mistake by dividing the cost of the present by 7 instead of 6. Each pupil paid $3.10 less than his share. What should be the cost of the present?
|
7 pupils |
6 pupils |
Number |
7 |
6 |
Value |
1 u |
1 u + 3.10 |
Total value |
7 u |
6 u + 18.60 |
Cost of the present if shared by 7 pupils
= 7 x 1 u
= 7 u
Cost of the present if shared by 6 pupils
= 6 x (1 u + 3.10)
= 6 u + 18.60
The total amount that the 7 pupils shared is the same as the total amount that the 6 pupils shared.
7 u = 6 u + 18.60
7 u - 6 u = 18.60
1 u = 18.60
Cost of the present
= 7 u
= 7 x 18.60
= $130.20
Answer(s): $130.20