Add 18/40 and 1/21
18/40 + 1/21 is 209/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
1/21 = 1 × 40/21 × 40 = 40/840 - Add the two like fractions:
378/840 + 40/840 = 378 + 40/840 = 418/840 - 418/840 simplified gives 209/420
- So, 18/40 + 1/21 = 209/420
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