Add 21/15 and 28/80
1st number: 1 6/15, 2nd number: 28/80
21/15 + 28/80 is 7/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 80 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 80 × 3 = 240,
28/80 = 28 × 3/80 × 3 = 84/240 - Add the two like fractions:
336/240 + 84/240 = 336 + 84/240 = 420/240 - 420/240 simplified gives 7/4
- So, 21/15 + 28/80 = 7/4
In mixed form: 13/4
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