Decimal Operations and Problem Solving

This video tutorial covers grade six practice problems on adding and subtracting decimals. It includes using base-10 diagrams for subtraction, aligning decimals for addition, and handling different decimal places. The tutorial also explores estimating costs in a store and calculating the volume of a rectangular prism using cubes. Finally, it demonstrates calculating the distance a car travels in a given time.

What is the first step when you cannot subtract a smaller decimal from a larger one in the same place value?

• Subtract directly without changes

• Ignore the smaller decimal

• Unbundle the next higher place value

• Add more to the smaller decimal

When adding decimals, why is it important to align the decimal points?

• To make the numbers look neat

• To ensure correct addition of place values

• To make subtraction easier

• To avoid carrying over

How can you subtract a decimal with more digits from one with fewer digits?

• Add zeros to the number with fewer digits

• Add more digits to the larger number

• Ignore the extra digits

• Subtract directly without changes

If a student claims you cannot subtract 1.97 from 20 because of different decimal places, what is the correct response?

• Agree, because 20 is a whole number

• Disagree, because you can add zeros to 20

• Agree, because subtraction is not possible

• Disagree, because you can only subtract whole numbers

What is the correct way to find the difference between 0.3 and 0.068?

• Align decimal points and subtract directly

• Add zeros to 0.3 and then subtract

• Ignore the smaller number

• Subtract without aligning decimal points

Elena wants to buy items costing $20.90 with a $20 budget. What should she do?

• Ignore the budget

• Estimate the cost again

• Borrow money

• Buy fewer items

How many pencils can Elena buy for $5 if each costs $0.32?

• 14 pencils

• 17 pencils

• 16 pencils

• 15 pencils

How do you calculate the number of half-centimeter cubes that fit in a prism?

• Multiply each dimension by 0.5 and add the results

• Divide each dimension by 0.5 and multiply the results

• Subtract 0.5 from each dimension and multiply

• Add each dimension and divide by 0.5

What is the volume of a rectangular prism with dimensions 7.5 cm, 12 cm, and 15.5 cm?

• 1350 cubic centimeters

• 1395 cubic centimeters

• 1500 cubic centimeters

• 1400 cubic centimeters

If a car travels 75 miles in 60 minutes, how far does it travel in 18 minutes?

• 25 miles

• 18 miles

• 20 miles

• 22.5 miles