Grade 5 - Number
Standard 5.N.2 - Practice estimating subtraction word problems by first rounding the numbers then finding the difference.
Included Skills: Estimation
Use estimation strategies in problem-solving contexts. • Provide a context for when estimation is used to: - make predictions. - check the reasonableness of an answer. - determine approximate answers. • Describe contexts in which overestimating is important. • Determine the approximate solution to a given problem not requiring an exact answer. • Estimate a sum or product, using compatible numbers. • Estimate the solution to a given problem, using compensation, and explain the reason for compensation. • Select and use an estimation strategy for a given problem. • Apply front-end rounding to estimate: - sums; e.g., 253 + 615 is more than 200 + 600 = 800. - differences; e.g., 974 – 250 is close to 900 – 200 = 700. - products; e.g., the product of 23 × 24 is greater than 20 × 20 (400) and less than 25 × 25 (625). - quotients; e.g., the quotient of 831 ÷ 4 is greater than 800 ÷ 4 (200).