Answer:
Warren paid $2.5 for the brush, $15 for the sketchbook and $20 for the paint set.
Step-by-step explanation:
If Warren went to the store with $41.5 and left with only $4 then the total amount he spent on the store was:
total spent = 41.5 - 4 = 37.5
Since he bought a brush, a sketchbook and a paint set we have:
brush + sketchbook + paint = 37.5
The prices of each item are related in the following manner:
brush = (1/6)*sketchbook
sketchbook = (3/4)*paint
brush = (1/6)*(3/4)*paint = (3/24)*paint = (1/8)*paint
Using these expressions on the one that represents the total value we will be abble to have only one variable, paint. We have:
(1/8)*paint + (3/4)*paint + paint = 37.5
(1/8)*paint + (6/8)*paint + (8/8)*paint = 37.5
(15/8)*paint = 37.5
paint = 37.5/(15/8) = 37.5*(8/15) = 20
brush = (1/8)*paint = (1/8)*20 = 2.5
sketchbook = (3/4)*paint = (3/4)*20 = 15
Warren paid $2.5 for the brush, $15 for the sketchbook and $20 for the paint set.
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, and then to know the value of r we just simply have to calculate the square root of 9, which is 3.