The cost price of 20 articles is the same as the selling price of x articles. If the profit is 25% then determine the value of x.

Answer: Option B

Explanation:

Let the Cost price of article is Rs. x

Required ratio =
\begin{aligned}
\frac{104\% \text{ of } x}{106\% \text{ of } x} \\
= \frac{104}{106} = \frac{52}{53} = 52:53
\end{aligned}

Answer: Option A

Explanation:

This type of question can be easily and quickly solved as following:

Let at Rs x it can earn 15% pr0fit
85:18700 = 115:x [as, loss = 100 -15, Profit = 100 +15]

x = (18700*115)/85
= Rs.25300

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:

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}

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}