A shopkeeper expects a gain of 45/2 % on his C.P. If his sale was Rs. 392, then find his profit.

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:

$$\begin{aligned} Gain\% = \\ \left( \frac{(100 + \text{common gain}\%)^2}{100} - 100 \right)\% \\ = \left( \frac{(100 + 10)^2}{100} - 100 \right)\% \\ = \left( \frac{12100 - 10000}{100}\right)\% \\ = 21\% \end{aligned}$$

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 B

Explanation:

Let the cost of Production = Rs. P
Then, as per question,

$$\begin{aligned} => \left( \frac{125}{100} *\frac{115}{100}*\frac{110}{100} * P \right) = 1265\\ => \frac{253}{160}P = 1265 \\ => P = 800 \end{aligned}$$

Answer: Option D

Explanation:

85 : 9 = 105 : x
x= (9×105/85)
= Rs 11.81