Add 16/21 and 18/40
16/21 + 18/40 is 509/420.
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,
16/21 = 16 × 40/21 × 40 = 640/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840 - Add the two like fractions:
640/840 + 378/840 = 640 + 378/840 = 1018/840 - 1018/840 simplified gives 509/420
- So, 16/21 + 18/40 = 509/420
In mixed form: 189/420
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