PSLE Tom and Rael have the same total number of coins. Tom has a number of fifty-cent coins and 62 ten-cent coins. The total mass of his coins is 0.524 kg. Rael has a number of fifty-cent coins and 112 ten-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 2.4 g heavier than each ten-cent coin. What is the total mass of Rael's coins in kg?
(a)
Since Tom has less ten-cent coins than Rael but both had the same number of coins, Tom had more money.
Both boys have the same number of coins. Since Tom has less ten-cent coins than Rael, it means that Tom has more fifty-cent coins than Rael. So Tom has more money.
Difference in the number of ten-cent coins.
= 112 - 62
= 50
Difference in the value of 1 ten-cent coin and 1 fifty-cent coin
= 50 - 10
= 40¢
Amount that Tom had more than Rael
= 50 x 40
= 2000¢
= $20
(b)
Difference in the mass between 50 ten-cent coins and 50 fifty-cent coins
= 50 x 2.4
= 120 g
= 0.12 kg
Total mass of Rael's coins
= 0.524 - 0.12
= 0.404 kg
Answer(s): (a) Tom, $20; (b) 0.404 kg