Mr Gan has fewer than 20 candies. He wants to pack them into plastic bags. If he packs 3 candies in each bag, he will have 4 extra candies left over. If he packs 5 candies in each bag, he will be short of 2 candies. How many candies does he have?

y = 13

Step-by-step explanation:

If Mr Gan packs 3 candies in each bag, he will have 4 extra candies left over. Therefore

3x + 4 = y

where 'x' represents the number of bags, and 'y' the total number of candies he has.

If Mr. Gan packs 5 candies in each bag, he will be short of 2 candies.

5x - 2 = y

To find the number of candies he has, we need to solve the system of equations ove:

3x + 4 = 5x - 2

6 = 2x

x = 3

Now, to find 'y':

5 (3) - 2 = y

y = 13

Therefore, Mr. Gan has 13 candies.