Add 28/30 and 21/72
28/30 + 21/72 is 49/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 30 × 12 = 360,
28/30 = 28 × 12/30 × 12 = 336/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Add the two like fractions:
336/360 + 105/360 = 336 + 105/360 = 441/360 - 441/360 simplified gives 49/40
- So, 28/30 + 21/72 = 49/40
In mixed form: 19/40
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