Answer:
•Calculator Use
Estimate sums and differences for positive proper fractions, n/d (numerator/denominator), where n ≤ d and 0 ≤ n/d ≤ 1. Use rounding to estimate answers when adding or subtracting proper fractions.
•mating Fractions by Rounding
This online calculator was originally set up to estimate by rounding fractions to the nearest 1/2. Fractions were rounded to 0, 1/2 or 1. For more precise estimating we added the ability to round fractions to the closest 1/4 or 1/8. See the section on "Value of Estimating Fractions" below.
•on "Value of Estimating Fractions" below.
Estimating sums and differences of fractions to the nearest 1/2
Fractions < 1/4 are rounded down to 0
Fractions ≥ 1/4 and ≤ 3/4 are rounded to 1/2
Fractions > 3/4 are rounded up to 1
Estimating sums and differences of fractions to the nearest 1/4
Fractions < 1/8 are rounded down to 0
Fractions ≥ 1/8 and < 3/8 are rounded to 2/8=1/4
Fractions ≥ 3/8 and < 5/8 are rounded to 4/8=2/4=1/2
Fractions ≥ 5/8 and < 7/8 are rounded to 6/8=3/4
Fractions ≥ 7/8 are rounded up to 8/8=1
Estimating sums and differences of fractions to the nearest 1/8
Fractions < 1/16 are rounded down to 0
Fractions ≥ 1/16 and < 3/16 are rounded to 2/16=1/8
Fractions ≥ 3/16 and < 5/16 are rounded to 4/16=2/8=1/4
Fractions ≥ 5/16 and < 7/16 are rounded to 6/16=3/8
Fractions ≥ 7/16 and < 9/16 are rounded to 8/16=4/8=1/2
Fractions ≥ 15/16 are rounded up to 16/16=8/8=1
