Sarah is conducting a science experiment. The directions tell her to mix 5 parts of substance A with every 3 parts of substance B . If she uses 15 milliters of substance B how many milliters of substance A should she use ?

use an equation of ratios to determine the amount of gas needed to fill the tank.

    0.2             0.8

  =    

288.75             x

                                                              231 gal

so, 0.2x = (0.8)(288.75 gal), and x = = 1155 gal.

                                                                0.2

it would take 1155 gal. to fill the tank.

the cost would be

1155 gal         $3

* = $3465   (answer)

      1           1 gal

hope this you

answer: the answer is d