Question

The manager of a snack bar buys bottled water in packs of 35 and candy bars in packs of 20. Then, she sells the items individually. Yesterday, she bought the same number of water bottles as candy bars to sell at the snack bar. If she bought the lowest number of items possible, how many packs of each item did she buy?

Answer 1

She bought 140 water bottles and 140 candy bars.

Answer 2

Answer: 4 packs of water and 7 packs of candy.

Explanation:

The data is:

The packs of water contain 35 units each.

The packs of candy contain 20 units each.

We have that the number of units is the same for both items, and the number is the lowest possible.

This means that we need to find the smallest common multiple between 35 and 20.

You can do it by hand: the multiples of 35 are:

35*1 = 35

35*2 = 70

35*3 = 105

35*4 = 140

Now, you may know that 140 is a multiple of 20, this is:

20*7 = 140

(the other 3 results are not multiples of 20)

So we have that the smallest common multiple between 35 and 20 is 140.

This means that she bought 140 units of each item, and:

140/35 = 4 packs of water

140/20 = 7 packs of candy