Question

Find S.P. when
(a) C.P. -840, gain = 20%​

Answer 1

Answer:

On finding sp when cp and profit or loss percent are given In this method you can use proportion or formula. If Profit % is given then selling price will be CP (100 + P%) SP = ------------------ 100 To find SP when loss % and CP are given CP (100 - L%) SP = ------------------ 100 Illustration 1 : Cost price = $450, Profit % = 5% find SP. Solution : As profit percent is given, we use the following formula. CP (100 + P%) SP = ------------------ 100 450 (100 + 5) SP = ------------------ 100 450 x 105 SP = ------------- 100 47250 SP = ----------- 100 ∴ Selling price = $472.50 ________________________________________________________________________ Illustration 2 : A bookseller sold 500 copies of a book at a profit of 20%. If a book costs him $15, find the selling price of the books. Solution: We have, Cost of one copy = $15 ∴ Cost of 500 copies = $(500 x 15) = $ 7500 It is given that the bookseller sold 500 copies at a profit of 20% ∴ Profit = 20% of C.P. = 2o/100 x 7500 = $1500 Now, S.P. = C.P. + Profit = 7500 + 1500 = $ 9000

Step-by-step explanation:

Answer 2

Solution:

Given:-

C.P. = 840

Gain % = 20 %

We have to find:-

S.P.

Let us firstly, find the Gain

As,

Gain % = ${\frac{Gain}{C.P.}}$×100

⟹ 20 % = ${\frac{Gain}{840}}$×100

⟹ ${\frac{20}{100}}$=${\frac{Gain}{840}}$

⟹${\frac{1}{5}}$=${\frac{Gain}{840}}$

⟹${\frac{1}{5}}$×840=Gain

⟹168 = Gain

Therefore, S.P. = C.P. + Gain

= 840 + 168

= 1008