At one point the miles are recorded as 15,121 when gas tank is 75% full. use a ratio equation to determine the miles per gallon the sedan averages. round your answer to the nearest whole number. due tomorrow show work if possible!

Looks like you are studying proportions.  A proportion is just an equation with two ratios that are equal.  For this problem the ratios we want to use are miles compared to gallons.  (I suggest you always first write your ratio in WORDS, then put in the numbers.)  miles         75    =    x            gallons         4         16 Do you know the CROSS PRODUCT PROPERTY?  We can use it to solve this proportion:     4x   =   75*16     4x   =   1200  4x/4   =   1200/4       x   =   300 miles Does this make sense?