Add 10/21 and 18/40
10/21 + 18/40 is 389/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
10/21 = 10 × 40/21 × 40 = 400/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840 - Add the two like fractions:
400/840 + 378/840 = 400 + 378/840 = 778/840 - 778/840 simplified gives 389/420
- So, 10/21 + 18/40 = 389/420
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