anonymous one year ago Annmarie can plow a field in 240 minutes. Gladys can plow a field 80 minutes faster. If they work together, how many minutes does it take them to plow the field?

1. anonymous

@amoodarya

2. amoodarya

$\frac{ A }{ 240 }=\frac{ G }{240-80 }\\A=\frac{3}{4}G$

3. anonymous

so it would be 160?

4. amoodarya

you have to find A+G

5. anonymous

how?

6. amoodarya

oh . sorry i had a mistake

7. anonymous

SO WHAT WE DO?

8. amoodarya

$\frac{ a }{ 240 }=\frac{ g }{160 }\\\frac{ a }{ 24 }=\frac{ g }{16 }\\\frac{ a }{ 3 }=\frac{ g }{2 }$

9. anonymous

then?

10. phi

I would use the idea of rate * time = amount of work rate is how much work you do per minute for example A does 1 field/240 minutes B goes 80 minutes faster so 1 field/160 minutes you can add the rates (1/240 + 1/160)* t = 1 field add the two fractions, and then find t

11. amoodarya

$\frac{ a }{ 3 }=\frac{ g }{ 2 }=\frac{ a+g }{x }$ find x

12. amoodarya

"phi" said it very simpler ,and clear

13. anonymous

96?

14. phi

yes, 96 minutes

15. anonymous

thank u guys