PSLE
Opal and Dana each had a plate of dough of the same mass for making croissants. The same mass of dough was used for each croissant. Opal made 39 croissants and had 435 g of dough left. Dana made 21 croissants and had 1.065 kg of dough left.

1. What was the mass of dough needed for each croissant?
2. With the remaining dough from both girls, how many more such croissants can be made at most? 

(a)
Difference between the number of croissants made by Opal and Dana
= 39 - 21
= 18

1 kg = 1000 g
1.065 kg = 1.065 x 1000 = 1065 g

Difference between the remaining dough left by Dana and Opal
= 1065 - 435
= 630 g

Mass of 18 croissants = 630 g

Mass of 1 croissant
= 630 ÷ 18
= 35 g

(b)
Total remaining dough left
= 1065 + 435
= 1500 g

Sets of 35 g
= 1500 ÷ 35
= 42 r 30

Number of croissants = 42

Answer(s): (a) 35 g; (b) 42