PSLE
Opal and Hazel 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 36 croissants and had 280 g of dough left. Hazel made 18 croissants and had 1.09 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 Hazel
= 36 - 18
= 18

1 kg = 1000 g
1.09 kg = 1.09 x 1000 = 1090 g

Difference between the remaining dough left by Hazel and Opal
= 1090 - 280
= 810 g

Mass of 18 croissants = 810 g

Mass of 1 croissant
= 810 ÷ 18
= 45 g

(b)
Total remaining dough left
= 1090 + 280
= 1370 g

Sets of 45 g
= 1370 ÷ 45
= 30 r 20

Number of croissants = 30

Answer(s): (a) 45 g; (b) 30