Question

Holly has tried to answer the question below. Write a sentence to explain the mistake that Holly has made. What answer should Holly have given? A number, x, truncated to 1 d.p. is 1.8 Write an equation to show the lower and upper bounds of x. 1.8 ≤x≤ 1.9​

Answer 1

Holly's mistake was in the incorrect bounds for a number truncated to 1 decimal place. The correct lower and upper bounds of the number should be 1.75 < x < 1.85, not 1.8 ≤ x ≤ 1.9.

Step-by-step explanation:

Holly made a mistake in determining the lower and upper bounds for a number truncated to 1 decimal place. When a number is rounded to 1 decimal place and has a value of 1.8, the actual number could be as low as just above 1.75 (since 1.75 would be rounded up to 1.8) and just below 1.85 (because 1.85 would be rounded up to 1.9).

Therefore, the correct equation to show the lower and upper bounds of x is 1.75 < x < 1.85.

Answer 2

Answer: Holly has not made a mistake, she has correctly identified the lower bound of x as 1.8 based on the fact that x truncated to 1 decimal place is 1.8. However, she has not identified the upper bound of x, which should be 1.9 based on the fact that x truncated to 1 decimal place could not be greater than 1.9. Therefore, the correct answer is: 1.8 ≤ x ≤ 1.9.

Step-by-step explanation: