Abag contains purple marbles and blue marbles, 49 in total. the number of purple marbles is 6 less than 4 times the number of blue marbles. how many purple marbles are there?

Purple = p

Blue = b

Step 1: Write as an algebraic equation.

p = 4b - 6

p + b = 49

Step 2: Rearrange p + b = 49 to make p the subject.

p + b = 49

p = 49 - b

Step 3: Write p = 4b - 6 and p = 49 - b into one equation.

p = 4b - 6 = 49 - b

Step 4: Move all b values onto one side.

p = 5b = 55

Step 5: Find the value of one blue marble.

5b = 55

b = 11

Step 6: If there are 11 blue marbles and there are 49 marbles in total, then find the number of purple marbles.

p = 49 - b

p = 49 - 11

p = 38

ANSWER:

There are 38 blue marbles.

I know I'm very late but I just wanted to give the answer for future reference. There are 19 purple marbles.

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