Question

Mai, Clare, and Noah are making signs to advertise the school dance. It takes Mai 6 minutes to complete a sign, it takes Clare 8 minutes to complete a sign, and it takes Noah 5 minutes to complete a sign. They keep working at the same rate for a half hour.

Will Mai and Clare complete a sign at the same time? Explain your reasoning.

Answer 1

• Yes, after 24 minutes

Explanation:

Mai spends 6 minutes on a sign and Clare spends 8 minutes

We need to find LCM(6,8) to determine if this number is smaller than 30 minutes, or greater

• LCM(6, 8) = LCM(2*3, 2*4) = 2*3*4 = 24 minutes

The answer is yes, after 24 minutes the will both complete a sign.