posted by on .

MS Wilkens went to the gas station to fill her car. Her gas tank is 20% full.
The cost of gas is \$4.29 per gallon. How much will itcost to fill the tank? Use the conversion 1 gallon=231 in cubed.
They showed a pic. of a tank with length=1.75ft
width=1.25 ft
height=11 in
I did v=bh
v=lwh v=1.75(1.25)11 v=24.0625 ft cubed

12 in=1ft
24.0625(12)=288.75 in cubed
288.75 in cubed/213 in cubed= 1.25 gallons
now I am cunfused

80% of 1.25= gallons left to fill tank
.80(125)= 1 gallon left to fill tank
1 gallon =\$4.29 It will cost\$4.29 to fill the tank

you cannot convert ft^3 to in^3 by multiplying by 12.

1 ft = 12 in, so
1 ft^3 = (12 in)^3 = 1728 in^3
24.0625 * 1728 = 415890 in^3 = 180 gal

That's some tank!

Ahh! You also did the volume wrong. You need to measure everything in either feet or inches, and you mixed them together.

Let's start over. The volume of the tank in in^3 is

21*15*11 = 3465 in^3 = 15 gals.

Now you should be able to make things come out right.

Ok I corrected my mistake and got that it would cost \$51.48, because it was 15 gallons she needed to get.
Is this correct now? Thank you