Respuesta :
all you have to do here is find the lcm.
the time it will take them too complete the lap at the same time is 12 minutes.
the time it will take them too complete the lap at the same time is 12 minutes.
Answer:
12 minutes
Step-by-step explanation:
We know that Susan will walk a lap in 4 minutes
Daphne will do it in 6 minutes
We have to find the Least Common Multiple for the minutes each of them will take, and it is a number that both numbers (4 and 6) will get as a resul of multiplying them by another number.
We are going to write down the miltiples of 4
4, 8, 12, 16, 20, 24,...
Now the multiples of 6
6, 12, 18, 24,...
Now we can see that there are several numbers that are multiples of 4 and also of 6 like in this case 12 and 24, but we are looking for the smallest number that is common for both numbers: in this case it is 12.
The reason to use the Least Common Multiple is that we know that Susan will finish a lap everytime multiples of 4 minutes pass, and Daphne will finish a lap at every multiple of 6 so when they have in common a multiple they both will be finishing a lap, in this case it will be Susan´s third lap and Daphne´s second lap but they will be crossing the starting line at the same time. And at 12 minutes it will be the first time they will complete a lap at the same time.