A piece of A4 paper is 11.3 inches by 15.7 inches.
What are the lower and upper bounds of its area, in square inches, correct to 1 dp?
Halve one decimal place is 0.05 inches
To find the lower bound for the area multiply the lower bounds together
i.e. 11.25 × 15.65 = 176.1 inches2 (1 d.p.)
To find the upper bound for the area multiply the upper bounds together
i.e. 11.35 × 15.75 = 178.7 inches2 (1 d.p.)
Henry ran 100m in 12.6 sec. both correct to 1 dp.
Find the UB and LB for his speed.