70.3k views
0 votes
Isobel and Marnie volunteer at a daycare center. Isobel works 3 hours for every 2 hours Marnie works. If the 2 girls together work 20 hours one month, how many hours does Isobel work?

User Waffl
by
8.4k points

1 Answer

4 votes
Isobel =I
Marnie =M
I(X) + M(X) = 20
3x + 2x =20
5x =20
divide by 5 both sides
5x/5 = 20/5
x = 4
then multiply I hours by 4 and M hours by 4

3(4) + 2(4) =20
12+ 8 = 20

Isobel worked a total of 12 hours and Marnie worked a total of 8.
Hope this helps

User Mmilleruva
by
8.7k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories