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 B

Explanation:

We Know,

\begin{aligned}
S.P. = \left( \frac{100+gain\%}{100} * C.P \right)\\
=> C.P. = \frac{100}{122.50}* 392 \\
= 320 \\

Profit = 392 -320 = Rs 72
\end{aligned}

Answer: Option B

Explanation:

Please remember
\begin{aligned}
S.P. = \left( \frac{100+gain\%}{100} * C.P \right)\\
\text{So, C.P. = }\left( \frac{100}{110} * 25.75 \right)\\
\text{When S.P. = 25.75 then } \\
Profit = 25.75 - 25 = Re. 0.75 \\

Profit\% = \frac{0.75}{25} * 100 = 3\%

\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 A

Explanation:

Let C.P.= Rs. 100.
Then, Profit = Rs. 320,
S.P. = Rs. 420.

New C.P. = 125% of Rs. 100 = Rs. 125
New S.P. = Rs. 420.

Profit = Rs. (420 - 125) = Rs. 295

Required percentage = (295/420) * 100
= 70%(approx)

Answer: Option D

Explanation:

Let the Cost Price of one article = Rs. 1
CP of x articles = Rs. x
CP of 20 articles = 20
Selling price of x articles = 20

Profit = 25% [Given]

\begin{aligned}
\Rightarrow \left (\dfrac{SP - CP }{CP}\right ) = \dfrac{25}{100} = \dfrac{1}{4}

& \Rightarrow \dfrac{\left(20-x \right )}{x} = \dfrac{1}{4} \\
& \Rightarrow 80 - 4x = x \\
& \Rightarrow 5x = 80 \nonumber \\
& \Rightarrow x = \dfrac{80}{5} = 16 \\

\end{aligned}