PSLE
Gabby and Erika each had a plate of dough of the same mass for making sandwiches. The same mass of dough was used for each sandwich. Gabby made 33 sandwiches and had 415 g of dough left. Erika made 15 sandwiches and had 1.225 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 Gabby and Erika
= 33 - 15
= 18

1 kg = 1000 g
1.225 kg = 1.225 x 1000 = 1225 g

Difference between the remaining dough left by Erika and Gabby
= 1225 - 415
= 810 g

Mass of 18 sandwiches = 810 g

Mass of 1 sandwich
= 810 ÷ 18
= 45 g

(b)
Total remaining dough left
= 1225 + 415
= 1640 g

Sets of 45 g
= 1640 ÷ 45
= 36 r 20

Number of sandwiches = 36

Answer(s): (a) 45 g; (b) 36