AI generatedNumberCourse skill

Checking whether an estimate is an overestimate or underestimate

Checking whether an estimate is an overestimate or underestimate.

  • Track how rounding changes the quantities.
  • For a product of positive numbers, rounding both down gives an underestimate.

Example 1

Estimate the product by rounding each factor down to a whole number. Is the estimate too high or too low?

EstimateBoth positive factors have been rounded down.
EstimateMaking both positive factors smaller makes the product smaller.
84, an underestimate.

Example 2

Estimate the product by rounding each factor down to a whole number. Is the estimate too high or too low?

EstimateBoth positive factors have been rounded down.
EstimateMaking both positive factors smaller makes the product smaller.
110, an underestimate.

Your turn

Question 1

Estimate the product by rounding each factor down to a whole number. Is the estimate too high or too low?

Check answer
EstimateBoth positive factors have been rounded down.
EstimateMaking both positive factors smaller makes the product smaller.
138, an underestimate.
Question 2

Estimate the product by rounding each factor down to a whole number. Is the estimate too high or too low?

Check answer
EstimateBoth positive factors have been rounded down.
EstimateMaking both positive factors smaller makes the product smaller.
168, an underestimate.
Question 3

Estimate the product by rounding each factor down to a whole number. Is the estimate too high or too low?

Check answer
EstimateBoth positive factors have been rounded down.
EstimateMaking both positive factors smaller makes the product smaller.
200, an underestimate.
Question 4

Estimate the product by rounding each factor down to a whole number. Is the estimate too high or too low?

Check answer
EstimateBoth positive factors have been rounded down.
EstimateMaking both positive factors smaller makes the product smaller.
234, an underestimate.
Question 5

Estimate the product by rounding each factor down to a whole number. Is the estimate too high or too low?

Check answer
EstimateBoth positive factors have been rounded down.
EstimateMaking both positive factors smaller makes the product smaller.
270, an underestimate.
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