To paint a room it takes mike 75 minutes, joan 60 minutes, and kyle 80 minutes when each person works alone. if all three work together how long will the painting take?

Mike takes 75 minutes to paint the room. So, in 1 minute the fraction of the room Mike paints is .

Likewise, in 1 minute the fraction of the room Joan paints is .

Lastly, in 1 minute the fraction of the room Kyle paints is .

Now, let be the number of minutes taken to paint the whole room when all three are working together.

Then, in 1 minute the fraction of the room the three paint will be .

This can be written as:

Therefore, If all three work together then they will finish the room in:

b

step-by-step explanation:

30 miles

step-by-step explanation:

we know that 60 seconds equals 1 minute and 60 minutes 1 hour

44 ft       60 sec     60 min     158400   ft

  *   *   =

1 sec       1 min       1 hour         hour

we know that there are 5280 ft per mile

158400   ft       1 mile         30 miles

  *   =

1   hour               5280 ft     1 hour

so in 1 hour   it can travel 30 miles