A man buys an article for Rs. 27.50 and sells it for Rs 28.60. Find his gain percent

Answer: Option C

Explanation:

So before solving this question we will get the C.P. and S.P. of 1 article to get the gain percent.

C.P. of 1 orange = 350/100 = Rs 3.50
S.P. of one orange = 48/12 = Rs 4 [note: divided by 12 as 1 dozen contains 12 items]
Gain = 4 - 3.50 = Rs 0.50
\begin{aligned}
Gain\% = \frac{0.50}{3.50}*100 \\
= \frac{100}{7}\%
= 14\frac{2}{7}\%
\end{aligned}

Answer: Option D

Explanation:

In this type of question, we will first find total C.P. of items, then total S.P. of items, then we will get gain or loss. From which we can easily calculate its percentage.

So lets solve it now.
\begin{aligned}
\text{So, C.P. of 1st transistor = }\\
\left( \frac{100}{120} * 840 \right) = 700 \\

\text{C.P. of 2nd transistor = }\\
\left( \frac{100}{96} * 960 \right) = 1000 \\

\text{Total C.P. = 1700 }\\
\text{Total S.P. = 1800 }\\
\text{Gain = 1800 - 1700 = 100}\\
\text{Gain% = } \left( \frac{100}{1700} * 100 \right) \\
= 5\frac{15}{17}\%
\end{aligned}

Answer: Option B

Explanation:

Let the cost price = Rs 100
then, Marked price = Rs 135

Required gain = 8%,
So Selling price = Rs 108
Discount = 135 - 108 = 27

Discount% = (27/135)*100 = 20%

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 B

Explanation:

Let the Cost Price of 1 item = Re. 1
Cost Price of 16 items = 16
Selling Price of 16 items = 12

Loss = 16 - 12 = Rs 4

Loss % = (4/16)* 100 = 25%