Maha Bodhi School SA1 2004 Math Question

A teacher has a bag of sweets. If she gives each pupil in her class 5 sweets, she will have 20 sweets left. If she gives them 8 sweets each, she will need to buy another 88 sweets. How many pupils are there in the class?

Solution



For every pupil that is given 8 sweets instead of 5, the teacher needs 3 more sweets.

From the above model, it can be seen that if she gives 8 sweets to each pupil instead of 5, she would need 108 more sweets.

3 “more sweets” ----- 1 (pupil)

1 “more sweet” ----- 1/3

108 “more sweets” ----- 1/3 x 108 = 36

Answer: There are 36 pupils in the class.