PSLE
Dylan and Xavier have the same total number of coins. Dylan has a number of ten-cent coins and 60 five-cent coins. The total mass of his coins is 0.534 kg. Xavier has a number of ten-cent coins and 80 five-cent coins.

1. Who has more money in coins? How much more? Give your answers in this format. (Eg Adam, $12)
2. Each ten-cent coin is 1.6 g heavier than each five-cent coin. What is the total mass of Xavier's coins in kg?

(a)
Since Dylan has less five-cent coins than Xavier but both had the same number of coins, Dylan had more money.

Both boys have the same number of coins. Since Dylan has less five-cent coins than Xavier, it means that Dylan has more ten-cent coins than Xavier. So Dylan has more money.

Difference in the number of five-cent coins.
= 80 - 60
= 20

Difference in the value of 1 five-cent coin and 1 ten-cent coin
= 10 - 5
= 5¢

Amount that Dylan had more than Xavier
= 20 x 5
= 100¢
= $1

(b)
Difference in the mass between 20 five-cent coins and 20 ten-cent coins
= 20 x 1.6
= 32 g
= 0.032 kg

Total mass of Xavier's coins
= 0.534 - 0.032
= 0.502 kg

Answer(s): (a) Dylan, $1; (b) 0.502 kg