Page 560 / Exercise #42
Find the marked price and the rate of discount for the
basketball system in this ad.
STEP 1.
Identify & record the “unknown” quantity being sought, and assign a
variable to represent it:
marked/original price = p & rate of discount = r
STEP 2.
Identify & record the known (given) quantities:
sale price: $599.99 & amount of discount:
$400
STEP 3.
Write an expression/equation relating the unknown & known info:
sale price = original price ! amt. of discount
i.e., $599.99 = p ! $400
(equation 1)
STEP 4.
Solve/simplify the first equation (add $400 to both sides):
$599.99 + $400 = p
$999.99 = p
then use:
discount rate = amt. of discount ÷ original price
i.e.,
r% =
(equation 2)
= 0.400004
. 0.40
convert decimal form to % (move decimal point 2 places to the right)...
Answer:
The marked (original) price was $999.99, and the
discount rate was 40%.