Add 28/30 and 7/21
28/30 + 7/21 is 19/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
28/30 = 28 × 7/30 × 7 = 196/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
7/21 = 7 × 10/21 × 10 = 70/210 - Add the two like fractions:
196/210 + 70/210 = 196 + 70/210 = 266/210 - 266/210 simplified gives 19/15
- So, 28/30 + 7/21 = 19/15
In mixed form: 14/15
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