Sumeet uses 0.4 gallons of gasoline each hour mowing lawns how much gas does he is in 4.2 hours

I believe you meant to ask how much gas does he use in 4.2 hours

we first need to calculate how much he uses in 1 minute.

60 min = 0.4 gallons

1 min = x

where x is the amount of gallons used per minute.

we cross multiply this equation:

60 x = 0.4

x = 0.4/60

we leave it is for now.

How many minutes are in 4.2 hours?

4 (60) + 0.2 (60) = y

where y is the number of minutes found in 4.2 hours. So after expanding the equation we have:

240 + 12 = y

252 = y

Now we multiply this number of minutes by the amount of gallons used for each minutes to get the total amount of fuel used.

252 * 0.4/60 = ?

100.8/60 = ?

100.8 divided by 60 = 1.68

Therefore in 4.2 hours, he uses 1.68 gallons of gasoline.