Question

Latoya created a factor tree and wrote the prime factorization of 90 shown below. A factor tree of 90. 90 branches to 9 and 10. 9 branches to 3 and 3. 10 branches to 2 and 5. The equation is 90 = 2 times 3 times 5. What is Latoya’s error?

Answer 1

Her equation is missing a factor of 3.

Explanation:

Her factor tree is correct. Her mistake is that she only used one of the factors of 3. The correct equation is 90 = 2 * 3 * 3 * 5

Answer 2

Answer: She omitted the other 3

Explanation:

90

∧

9 10

∧ ∧

3 3 2 5

90 = 2×3×3×5

There are TWO threes. Latoya only included one of them.