Carlos has 32 iris bulbs and 40 tulip bulbs. He wants to plant them in rows with one type of bulb in each row. He wants all rows to have the same number of bulbs. The greatest number of bulbs he can plant in each row is __________.

What is the greatest common factor of 32 and 40?

is the answer 8

Right.

To find the greatest number of bulbs Carlos can plant in each row, we need to find the greatest common divisor (GCD) of 32 and 40.

One way to find the GCD is to list all the factors of each number and find the largest one that they have in common.

The factors of 32 are: 1, 2, 4, 8, 16, 32.
The factors of 40 are: 1, 2, 4, 5, 8, 10, 20, 40.

From this, we can see that the greatest common divisor of 32 and 40 is 8.

Therefore, the greatest number of bulbs Carlos can plant in each row is 8.