A shopkeeper sold an article for Rs 2564.36. Approximately what was his profit percent if the cost price of the article was Rs 2400

Answer: Option A

Explanation:

Suppose he bought 5 kg and 3 kg of tea.
Cost Price = Rs. (5 x 18 + 3 x 20) = Rs. 150.
Selling price = Rs. (8 x 21) = Rs. 168.
Profit = 168 - 150 = 18

So, Profit % = (18/150) * 100 = 12%

Answer: Option C

Explanation:

Let the cost price 1 article = Re 1
Cost price of x articles = x
S.P of x articles = 20

Gain = 20 -x

\begin{aligned}
=> 25 = \left( \frac{20-x}{x} * 100 \right) \\
=> 2000 - 100x = 25 x \\
=> x = 16
\end{aligned}

Answer: Option C

Explanation:

We need to get the Total selling price to solve this question. Because after getting selling price we can get profit or loss, then we can calculate profit% or loss%

So lets solve this:

Price Received by selling one fourth of the material at a loss of 20% =
(1/4) * 600 * (80/100) = Rs. 120

Price Received by remaining material at a gain of 10% =
(3/4) * 600 * (110/100) = Rs. 495 [Note: 1-(1/4) = 3/4]

Total Selling Price = 120 + 465 = Rs. 615

Profit = 615 - 600 = 15

\begin{aligned}
Profit\% = \left( \frac{Gain}{Cost} * 100 \right)\% \\
= \left( \frac{15}{600} * 100 \right)\% \\
= \frac{5}{2}\% = 2\frac{1}{2}\%
\end{aligned}

Answer: Option D

Explanation:

Here always remember, when ever x% loss,
it means S.P. = (100 - x)% of C.P
when ever x% profit,
it means S.P. = (100 + x)% of C.P

So here will be (100 - x)% of C.P.
= 80% of 1200
= 80/100 * 1200
= 960

Answer: Option D

Explanation:

So we have C.P. = 27.50
S.P. = 28.60

Gain = 28.60 - 27.50 = Rs. 1.10

\begin{aligned}
Gain\% = \left( \frac{Gain}{Cost} * 100 \right)\% \\
= \left( \frac{1.10}{27.50} * 100 \right)\% = 4\%
\end{aligned}