RRB ALP CBT I 11 Feb 2026 Shift 1 Paper

Concept:Use the net multiplier method to combine a percentage increase and successive discounts into one single factor.Explanation:Let the initial selling price be $100$ units.After a $30\%$ increase, the price becomes $100 \times \frac{130}{100} = 130$ units.After the first $10\%$ discount, the price becomes $130 \times \frac{90}{100} = 117$ units.After the second $10\%$ discount, the price becomes $117 \times \frac{90}{100} = 105.3$ units.Net change in selling price $= 105.3 - 100 = 5.3$ units.Net percentage change $= \frac{5.3}{100} \times 100 = 5.3\%$.Since the final value is greater than the initial value, this is a net increase.As a shortcut, net multiplier $= 1.30 \times 0.90 \times 0.90 = 1.053$, which directly gives a $5.3\%$ increase.Answer:The selling price increases by $5.3\%$.The correct option is B.