Question 1: Estimate the product of 3.24 and 7.89 by rounding to the nearest whole number before multiplying.

Answer: 25

Question 2: Calculate the approximate value of 5.67 × 2.89 using estimation. Show your working.

Answer: 16.4

Question 3: A recipe calls for 0.75 kg of sugar per batch. If a bakery makes about 12 batches, estimate the total sugar needed.

Answer: 9 kg

Question 4: Estimate the cost of 8.49 liters of juice if each liter costs approximately €1.35. Show your reasoning.

Answer: €11

Question 5: A manufacturer produces 4.76 meters of fabric per roll. Estimate the total fabric produced if 15 rolls are used, rounding to the nearest whole number first.

Answer: 71 m

Question 6: Estimate the total cost of buying 6 items priced at about €3.49 each, using estimation. Show your working.

Answer: €21

Question 7: A garden covers approximately 2.75 hectares. Estimate the area in hectares if the actual size is about 2.8 hectares, using estimation.

Answer: about 3 hectares

Question 8: Estimate the total weight if 3.89 kg of apples are divided into 4 bags. Round to the nearest whole number first before dividing.

Answer: 4 kg

Question 9: A car travels approximately 45.3 km per hour. Estimate how far it travels in 3.75 hours, rounding to the nearest ten before calculating.

Answer: 170 km

Question 10: A batch of 0.86 liters of paint is used to paint 3 walls. Estimate how much paint is used per wall, rounding to the nearest tenth.

Answer: 0.3 liters

Question 11: Estimate the product of 9.74 and 6.2 by rounding each to one decimal place, then multiply.

Answer: 60

Question 12: Identify and correct the mistake in estimating: "Since 4.68 × 2.97 is approximately 5 × 3 = 15," is this estimate accurate? Explain.

Answer: No, because 4.68 and 2.97 round to 5.0 and 3.0, making the estimate reasonable. The mistake is assuming perfect accuracy without considering rounding errors.