A book was sold for Rs 27.50 with a profit of 10%. If it were sold for Rs. 25.75, then would have been percentage of profit and loss ?

Answer: Option C

Explanation:

Let original Cost price is x
Its Selling price = 105/100 * x = 21x/20
New Cost price = 95/100 * x = 19x/20
New Selling price = 110/100 * 19x/20 = 209x/200
[(21x/20) - (209x/200)] = 1

=> x = 200

Answer: Option C

Explanation:

As question states that rate was of pair of articles,

So rate of One article = 37.40/2 = Rs. 18.70

Let Marked price = Rs X
then 85% of X = 18.70

=> X = 1870/85 = 22

Answer: Option B

Explanation:

We know, C.P. = 5000
S.P. = 4000
Loss = 5000 - 4000 = 1000
\begin{aligned}
Loss\% = \left( \frac{Loss}{Cost} * 100 \right)\% \\
= \left( \frac{1000}{5000} * 100 \right)\% = 20\%
\end{aligned}

Answer: Option A

Explanation:

Please note in this type of questions, get the value of 1 kg to solve this question, lets solve it.

C.P. of 1 Kg = 420/70 = Rs. 6
Selling Price = 6.50
Gain = Rs. 0.50

\begin{aligned}
Gain\% = \frac{.50}{6}*100 \\
= 8\frac{1}{3}\%
\end{aligned}

Answer: Option C

Explanation:

Let the new S.P. be x, then.
(100 - loss%):(1st S.P.) = (100 + gain%):(2nd S.P.)

\begin{aligned}
=>\left( \frac{95}{1140} = \frac{105}{x} \right) \\

=> x = 1260
\end{aligned}