RRB Assistant Loco Pilot and Technician Model Paper 17 with key

Let Length = 2
Let breadth = 1
Area of rectangle
= Length × breadth = 2 × 1 = 2
Length increases by 10%
= 110% of 2 = $\frac{110}{100}$ × 2 = 2.2
breadth decreases by 10% = 90% of 1 = $\frac{90}{100}$ × 1 = 0.9
New area of rectangle
= 2.2 × 0.9 = 1.98
Change in Area = 2 − 1.98 = 0.02
Percentage Change = $\frac{\mathrm{Change}\mathrm{in}\mathrm{Area}}{\mathrm{Initial}\mathrm{Area}}$ × 100
= $\frac{0.02}{2}$ × 100 = 1% decrease