PSLE Daniel and Charlie have the same total number of coins. Daniel has a number of fifty-cent coins and 45 five-cent coins. The total mass of his coins is 0.996 kg. Charlie has a number of fifty-cent coins and 85 five-cent coins.
- Who has less money in coins? How much less? Give your answers in this format. (Eg Adam, $12)
- Each fifty-cent coin is 1.3 g heavier than each five-cent coin. What is the total mass of Charlie's coins in kg?
(a)
Both boys have the same number of coins. Since Charlie has more five-cent coins than Daniel, it means that Charlie has less fifty-cent coins than Daniel. So Charlie has less money.
Difference in the number of five-cent coins.
= 85 - 45
= 40
Difference in the value of 1 five-cent coin and 1 fifty-cent coin
= 50 - 5
= 45¢
Amount that Charlie had less than Daniel
= 40 x 45
= 1800¢
= $18
(b)
Difference in the mass between 40 five-cent coins and 40 fifty-cent coins
= 40 x 1.3
= 52 g
= 0.052 kg
Total mass of Charlie's coins
= 0.996 - 0.052
= 0.944 kg
Answer(s): (a) Daniel, $18; (b) 0.944 kg