PSLE
Simon and Cody have the same total number of coins. Simon has a number of fifty-cent coins and 54 twenty-cent coins. The total mass of his coins is 1.326 kg. Cody has a number of fifty-cent coins and 94 twenty-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 3.3 g heavier than each twenty-cent coin. What is the total mass of Cody's coins in kg?

(a)
Since Simon has less twenty-cent coins than Cody but both had the same number of coins, Simon had more money.

Both boys have the same number of coins. Since Simon has less twenty-cent coins than Cody, it means that Simon has more fifty-cent coins than Cody. So Simon has more money.

Difference in the number of twenty-cent coins.
= 94 - 54
= 40

Difference in the value of 1 twenty-cent coin and 1 fifty-cent coin
= 50 - 20
= 30¢

Amount that Simon had more than Cody
= 40 x 30
= 1200¢
= $12

(b)
Difference in the mass between 40 twenty-cent coins and 40 fifty-cent coins
= 40 x 3.3
= 132 g
= 0.132 kg

Total mass of Cody's coins
= 1.326 - 0.132
= 1.194 kg

Answer(s): (a) Simon, $12; (b) 1.194 kg