Question

if josh can wash a car in 2 hours and edward can do it in 3, how fast can they do it together?

Answer 1

I think it so:
u must consider the hours in 1 minute this mean only this 1 divide by hours in minutes
ok u must follow only the steps:

Answer 2

\[(\frac{ 1 }{ 120 }+\frac{ 1 }{ 180 })*x=1\]

Answer 3

now I multiply the numbers in parentetes the denominator must be the same:
so:

Answer 4

\[\frac{ 1 }{ 120 }*\frac{ 3 }{ 3 } ~~ then~~ \frac{ 1 }{ 180}*\frac{ 2 }{ 2 } \]

Answer 5

\[(\frac{ 3 }{ 360}+\frac{ 2 }{ 360})=\frac{ 5 }{ 360 }\]

Answer 6

Now we have:

Answer 7

\[(\frac{ 5 }{ 360 })*x=1 \]

Answer 8

Now I divede both side with 5/360

Answer 9

it become:

Answer 10

\[x=1:(\frac{ 5 }{ 360 })\]

Answer 11

now we have this rule 1/2:1/2 in this case the dived became * and 1/2 became inverted

Answer 12

\[\frac{ 1 }{ 2 }*\frac{ 2 }{ 1}=\frac{ 2 }{ 2 }=1\]

Answer 13

\[x=1*\frac{ 360}{ 5 }=\frac{ 360 }{ 5 }=72\]

Answer 14

72 minutes.