An art gallery has 18 paintings and 4 photographs displayed in equal rows on a wall, with the same number of each type of art in each row. which of the following could be the number of rows?
a 2 rows, b 3 rows, c 4 rows, d 6 rows

The question is asking us to determine the number of rows in which 18 paintings and 4 photographs could be displayed, such that there should be the same number of each type of art in each row. First we have to find the GCF ( the Greatest Common Factor ) of 18 and 4. 18 = 2 * 3 * 3 and 4 = 2 * 2. The prime factors of 18 are 2 and 3 and the prime factor of 4 is 2. Therefore GCF ( 18, 4 ) = 2. There could be 2 rows, with 9 paintings and 2 photographs in each. A . 2 rows.

The answer is why would a teacher ask that

Many things that seem threatening in the dark become welcoming when we shine light on them