PSLE
Linda and Shiyun each had a plate of dough of the same mass for making sandwiches. The same mass of dough was used for each sandwich. Linda made 40 sandwiches and had 400 g of dough left. Shiyun made 22 sandwiches and had 1.03 kg of dough left.

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

(a)
Difference between the number of sandwiches made by Linda and Shiyun
= 40 - 22
= 18

1 kg = 1000 g
1.03 kg = 1.03 x 1000 = 1030 g

Difference between the remaining dough left by Shiyun and Linda
= 1030 - 400
= 630 g

Mass of 18 sandwiches = 630 g

Mass of 1 sandwich
= 630 ÷ 18
= 35 g

(b)
Total remaining dough left
= 1030 + 400
= 1430 g

Sets of 35 g
= 1430 ÷ 35
= 40 r 30

Number of sandwiches = 40

Answer(s): (a) 35 g; (b) 40