Multiple choice

Sally has 5 inches pieces of toy train and Chloe has 7 inches pieces of train track. How much of each piece would each child need to build tracks that are equal in length?

  1. 30 inches

  2. 32 inches

  3. 34 inches

  4. 35 inches

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Sally has 5-inch pieces and Chloe has 7-inch pieces. To build equal length tracks, find the smallest length divisible by both 5 and 7. Since 5 and 7 are co-prime, LCM(5, 7) = 35 inches. Sally needs 7 pieces (35 ÷ 5) and Chloe needs 5 pieces (35 ÷ 7).