During a promotional event a sporting goods store gave a free t-shrit to every 8th customer and a free water bottle to every 10th customer which customer has the first to get a free t-shirt and a free water bottle

Given

During a promotional event

A sporting goods store gave a free t-shrit to every 8th customer and a free water bottle to every 10th customer.

Find out which customer has the first to get a free t-shirt and a free water bottle.

To proof

Definition of LCM (Least common multiple)

The LCM of two numbers is the smallest number that they both divide evenly into.

As given in the equation

A sporting goods store gave a free t-shrit to every 8th customer and a free water bottle to every 10th customer.

Let take 8 be as one number and 10 be as another number.

LCM (8,10) = 2 * 2 * 2 * 5

= 40

Also

A sporting goods store gave a free t-shrit to every 8th customer and a free water bottle to every 10th customer.

This is shown in the table given below.

As shown in the table the common value is 40.

Therefore

The first to get a free t-shirt and a free water bottle is 40th customer.

Hence proved