Add 21/15 and 81/16
1st number: 1 6/15, 2nd number: 5 1/16
21/15 + 81/16 is 517/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 16 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 15 × 16 = 240,
21/15 = 21 × 16/15 × 16 = 336/240 - Likewise, for the 2nd fraction, since 16 × 15 = 240,
81/16 = 81 × 15/16 × 15 = 1215/240 - Add the two like fractions:
336/240 + 1215/240 = 336 + 1215/240 = 1551/240 - 1551/240 simplified gives 517/80
- So, 21/15 + 81/16 = 517/80
In mixed form: 637/80
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