PSLE
Ryan and Fabian have the same total number of coins. Ryan has a number of fifty-cent coins and 60 ten-cent coins. The total mass of his coins is 1.366 kg. Fabian has a number of fifty-cent coins and 100 ten-cent coins.

1. Who has more money in coins? How much more? Give your answers in this format. (Eg Adam, $12)
2. Each fifty-cent coin is 3.9 g heavier than each ten-cent coin. What is the total mass of Fabian's coins in kg?

(a)
Since Ryan has less ten-cent coins than Fabian but both had the same number of coins, Ryan had more money.

Both boys have the same number of coins. Since Ryan has less ten-cent coins than Fabian, it means that Ryan has more fifty-cent coins than Fabian. So Ryan has more money.

Difference in the number of ten-cent coins.
= 100 - 60
= 40

Difference in the value of 1 ten-cent coin and 1 fifty-cent coin
= 50 - 10
= 40¢

Amount that Ryan had more than Fabian
= 40 x 40
= 1600¢
= $16

(b)
Difference in the mass between 40 ten-cent coins and 40 fifty-cent coins
= 40 x 3.9
= 156 g
= 0.156 kg

Total mass of Fabian's coins
= 1.366 - 0.156
= 1.21 kg

Answer(s): (a) Ryan, $16; (b) 1.21 kg