PSLE Fabian and Ethan have the same total number of coins. Fabian has a number of fifty-cent coins and 52 twenty-cent coins. The total mass of his coins is 0.606 kg. Ethan has a number of fifty-cent coins and 102 twenty-cent coins.
- Who has more money in coins? How much more? Give your answers in this format. (Eg Adam, $12)
- Each fifty-cent coin is 1.7 g heavier than each twenty-cent coin. What is the total mass of Ethan's coins in kg?
(a)
Since Fabian has less twenty-cent coins than Ethan but both had the same number of coins, Fabian had more money.
Both boys have the same number of coins. Since Fabian has less twenty-cent coins than Ethan, it means that Fabian has more fifty-cent coins than Ethan. So Fabian has more money.
Difference in the number of twenty-cent coins.
= 102 - 52
= 50
Difference in the value of 1 twenty-cent coin and 1 fifty-cent coin
= 50 - 20
= 30¢
Amount that Fabian had more than Ethan
= 50 x 30
= 1500¢
= $15
(b)
Difference in the mass between 50 twenty-cent coins and 50 fifty-cent coins
= 50 x 1.7
= 85 g
= 0.085 kg
Total mass of Ethan's coins
= 0.606 - 0.085
= 0.521 kg
Answer(s): (a) Fabian, $15; (b) 0.521 kg