# I have 3 pints of oil and 12 gals of gas. the lawnmower uses 0.5 pints of oil and 1.5 gals of gas. How many days can I mow the lawns?

pohnpei397 | Certified Educator

What you have to do is divide the number of pints of oil and gas that you have by the amount that is used each day that you mow the lawns.  Then you have to take the smaller number and that is how many days you can mow.

So first we divide 3 by .5.  When you do this, you end up with 6.  This means that you have enough oil to mow the lawns for 6 days.

Next, we divide 12 by 1.5.  When you do this, you end up with 8.  This means that you have enough gas to mow the lawns for 8 days.

But we have to take the smaller number because after 6 days you will be out of oil even though you have enough gas for two more days.

So the answer is 6 days.

neela | Student

The problem is how many days you can use the stock od 3pints of pil and 12 gallons of gas at the rate 0.5pints of oil and 1.5 of gas.

Since  need both oil and gas together, we can calculate which exhauste earlier.

The number of days the oil exhausts = oil stock/oil cosumption per day = 3/0.5 = 6days.

The number of ays gas exhausts =stock of gas consumption of gas per day = 12/1.5 = 8.

So at the rate of (0.5p + 1.5g) per day   both  oil and gas could be used for 6 days and the oil  is exhausted fully on the 6th day and remaining stock is  (3p+12g)-6(0.5+1.5g) = (6-6)p+(12-9)g  = 0p+3g = 0pint of oil and 3gallon of gasat the end of the 6th day.