Answer:
Lower bound = 5.2
Upper bound = 5.4
Step-by-step explanation:
If a= 4.2 to (1dp):
Upper bound = 4.2 + 0.05 = 4.25
Lower bound = 4.2 - 0.05 = 4.15
If b = 18 (to the nearest whole number)
Upper bound = 18 + 0.5 = 18.5
Lower bound = 18 - 0.5 = 17.5
Therefore:
Lower bound of ((a+b)/a) = ((4.15 + 17.5) / 4.15) = 5.2 to 1 decimal place
Upper bound of ((a+b)/a) = ((4.25 + 18.5) / 4.25) = 5.4 to 1 decimal place
The upper and lower bound are calculated to one decimal place.
