Chapter 10 Exam

Two calibrated containers hold 2.52 L and 1.23 L. A report says their combined amount is 3.85 L. Is that report accurate?

The assigned question is: “Two calibrated containers hold 2.52 L and 1.23 L. A report says their combined amount is 3.85 L. Is that report accurate?” A learner wrote: “2.52 + 1.23 = 4.75. I used this intermediate value to finish the assigned problem.” Identify a concrete invalid step or assumption. Work out the correct result and explain why it is valid.

Two calibrated containers hold 2.53 L and 1.24 L. A report says their difference is 1.39 L. Is that report accurate?

The assigned question is: “Two calibrated containers hold 2.53 L and 1.24 L. A report says their difference is 1.39 L. Is that report accurate?” A learner wrote: “2.53 − 1.24 = 2.29. I used this intermediate value to finish the assigned problem.” Identify a concrete invalid step or assumption. Work out the correct result and explain why it is valid.

A trainee claims 4.33 × 0.1 must exceed 4.33. Assess the claim using an exact product and a reason.

The assigned question is: “A trainee claims 4.33 × 0.1 must exceed 4.33. Assess the claim using an exact product and a reason.” A learner wrote: “I shifted the decimal in 4.33 in the wrong direction when finding the requested fraction; I got Yes; the original statement is correct..” Identify a concrete invalid step or assumption. Work out the correct result and explain why it is valid.

A trainee claims 4.34 × 0.25 must exceed 4.34. Assess the claim using an exact product and a reason.

The assigned question is: “A trainee claims 4.34 × 0.25 must exceed 4.34. Assess the claim using an exact product and a reason.” A learner wrote: “I counted the hundredths in 4.34 as tenths during multiplication; I obtained Yes; the original statement is correct..” Identify a concrete invalid step or assumption. Work out the correct result and explain why it is valid.

An assistant reports 0.58 L per jar when 1.92 L are split among 4 jars. Find the actual equal share.

The assigned question is: “An assistant reports 0.58 L per jar when 1.92 L are split among 4 jars. Find the actual equal share.” A learner wrote: “1.92 ÷ 4 = 1.48. I used this intermediate value to finish the assigned problem.” Identify a concrete invalid step or assumption. Work out the correct result and explain why it is valid.

An assistant reports 0.59 L per jar when 2.94 L are split among 6 jars. Find the actual equal share.

The assigned question is: “An assistant reports 0.59 L per jar when 2.94 L are split among 6 jars. Find the actual equal share.” A learner wrote: “2.94 ÷ 6 = 1.49. I used this intermediate value to finish the assigned problem.” Identify a concrete invalid step or assumption. Work out the correct result and explain why it is valid.

Which operation finds how many 0.1-meter segments fit into 25 meters, multiplication or division? Compute and check.

The assigned question is: “Which operation finds how many 0.1-meter segments fit into 25 meters, multiplication or division? Compute and check.” A learner wrote: “25 ÷ 0.1 = 251. I used this intermediate value to finish the assigned problem.” Identify a concrete invalid step or assumption. Work out the correct result and explain why it is valid.

Which operation finds how many 0.25-meter segments fit into 26 meters, multiplication or division? Compute and check.

The assigned question is: “Which operation finds how many 0.25-meter segments fit into 26 meters, multiplication or division? Compute and check.” A learner wrote: “26 ÷ 0.25 = 105. I used this intermediate value to finish the assigned problem.” Identify a concrete invalid step or assumption. Work out the correct result and explain why it is valid.