Mark and Aki are building Hot Wheels tracks. Mark has 4-inch pieces to make his track, and Aki has 10-inch pieces to make his track. How long will their tracks be when they finish the same length?

1 answer

To find out when Mark and Aki's tracks will be the same length, we can use the least common multiple (LCM) of their track piece lengths.

Mark has 4-inch pieces, and Aki has 10-inch pieces. We need to find the LCM of 4 and 10.

  1. Prime factorization:

    • The prime factorization of 4 is \(2^2\).
    • The prime factorization of 10 is \(2^1 \times 5^1\).
  2. Determining the LCM:

    • For the LCM, we take the highest power of each prime number that appears in the factorizations.
    • For \(2\), the highest power is \(2^2\) (from 4).
    • For \(5\), the highest power is \(5^1\) (from 10).

So, the LCM is calculated as: \[ LCM = 2^2 \times 5^1 = 4 \times 5 = 20 \]

Therefore, the length of the tracks when they finish the same length will be 20 inches.