Due to an increase in 30% in the price of eggs, 3 eggs less are available for Rs. 7.80. Find the present rate of eggs per dozen.

Answer: Option B

Explanation:

2/50 * 100 = 1/25 * 100 = 4 %

Answer: Option D

Explanation:

$$\begin{aligned} n(A) = \left(\frac{60}{100}*96\right) = \frac{288}{5} \\ n(B) = \left(\frac{30}{100}*96\right) = \frac{144}{5} \\ n(A\cap B) = \left(\frac{15}{100}*96\right) = \frac{72}{5} \\ \text{People who have either or both lunch} \\ n(A\cup B) = \frac{288}{5}+\frac{144}{5}-\frac{72}{5} \\ = \frac{360}{5} = 72 \end{aligned}$$

So People who do no have either lunch were = 96 -72
= 24

Answer: Option A

Explanation:

Clue: Answer will be 5% of 1000 - 4% of 1000

Answer: Option C

Explanation:

(1/4) * (1/3) * (2/5) * x = 15 then x = 15 * 30 = 450
40% of 450 = 180

Answer: Option C

Explanation:

Failed in mathematics, n(A) = 34
Failed in English, n(B) = 42

$$\begin{aligned} n(A\cup B) = n(A)+n(B)-n(A\cap B) \\ = 34+42-20 = 56 \\ \text{Failed in either or both subjects are 56} \\ \text{Percentage passed = }(100-56)\% \\ = 44\% \end{aligned}$$