Add 20/21 and 18/40
20/21 + 18/40 is 589/420.
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,
20/21 = 20 × 40/21 × 40 = 800/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840 - Add the two like fractions:
800/840 + 378/840 = 800 + 378/840 = 1178/840 - 1178/840 simplified gives 589/420
- So, 20/21 + 18/40 = 589/420
In mixed form: 1169/420
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