Question

Kristin’s three-year old sister is trying to arrange pink and red Starbursts in rows. She has 360 pink Starbursts and 150 red Starbursts. She wants to arrange them in rows so that there are either only pink or only red Starbursts in each row, and so that each row has the same number of Starburts. What is the least number of rows she can make?

Answer 1

To find the least number of rows she can make will be found by finding the biggest way to divide these into equal groups (greatest common factor).

You can use prime factorizations of each number to find the gcf.

150 - 2 x 3 x 5 x 5
360 - 2 x 2 x 2 x 3 x 3 x 5

The common prime numbers are 2 x 3 x 5

You can make 12 (360/30) rows of pink and 5 (150/30) rows of red.