Question 1: Arrange the following decimals in ascending order: 4.56, 4.65, 4.56, 4.61.

Answer: 4.56, 4.56, 4.61, 4.65

Question 2: What is the decimal value of 7.88 and 7.8? Which is larger? Show your working.

Answer: 7.88 is larger because 88 > 80 in the hundredths place.

Question 3: Order these decimals from largest to smallest: 3.999, 3.99, 3.999, 4.0.

Answer: 4.0, 3.999, 3.999, 3.99

Question 4: In the decimal numbers 0.456, 0.465, 0.456, 0.464, which is the smallest and which is the largest? Explain your reasoning.

Answer: Smallest: 0.456; Largest: 0.465, because comparing digit by digit shows 0.456 < 0.464 < 0.465.

Question 5: Calculate the difference between 6.789 and 6.798. Show your working.

Answer: 6.798 - 6.789 = 0.009

Question 6: If a thermometer shows 23.45°C and another shows 23.54°C, which reading is higher? How do you know?

Answer: 23.54°C is higher because 54 hundredths is greater than 45 hundredths.

Question 7: Construct a set of four decimals with the same number of digits after the decimal point, and arrange them in decreasing order.

Answer: Sample: 5.67, 5.76, 5.65, 5.60; ordered as 5.76, 5.67, 5.65, 5.60.

Question 8: Identify and correct the mistake: Ordering 1.234, 1.243, 1.324, 1.342 as 1.243, 1.234, 1.342, 1.324.

Answer: The correct order is 1.234, 1.243, 1.324, 1.342. The mistake was placing 1.243 before 1.234; since 1.234 < 1.243, that order is incorrect.

Question 9: Order the numbers 9.876, 9.867, 9.876, 9.865 from smallest to largest.

Answer: 9.865, 9.867, 9.876, 9.876

Question 10: A scientist measures two substances: 0.999 and 1.099. Which is bigger and why?

Answer: 1.099 is bigger because 1.099 > 0.999.

Question 11: Challenge: Construct four decimals with the same number of decimal places, where the middle two are equal, and order them from least to greatest.

Answer: Example: 2.34, 2.34, 2.35, 2.36; ordered as 2.34, 2.34, 2.35, 2.36.