Answer:
The minimum of a - b is 41.325
Step-by-step explanation:
Let us solve the question using upper and lower boundaries
∵ a = 49.0 rounded to 1 decimal place
∵ 1 decimal place means 0.1
→ Divide 0.1 by 2
∵ 0.1 ÷ 2 = 0.05
→ Add 0.05 to the rounded number to get the upper boundary
∵ 49.0 + 0.05 = 49.05
∴ The upper boundary = 49.05
→ Subtract 0.05 from the rounded number to get the lower boundary
∵ 49.0 - 0.05 = 48.95
∴ The lower boundary = 48.95
∴ The range of a is 48.95 ≤ a < 49.05
∵ b = 7.62 rounded to 2 decimal places
∵ 2 decimal place means 0.10
→ Divide 0.01 by 2
∵ 0.01 ÷ 2 = 0.005
→ Add 0.005 to the rounded number to get the upper boundary
∵ 7.62 + 0.005 = 7.625
∴ The upper boundary = 7.625
→ Subtract 0.005 from the rounded number to get the lower boundary
∵ 7.62 - 0.005 = 7.615
∴ The lower boundary = 7.615
∴ The range of b is 7.615 ≤ b < 7.625
To find the minimum value of a - b, use the smallest value of a and the greatest value of b
∵ The minimum of a - b = lower boundary of a - upper boundary of b
∴ The minimum of a - b = 48.95 - 7.625
∴ The minimum of a - b = 41.325
∴ The minimum of a - b is 41.325
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