Add 7/21 and 2/10
7/21 + 2/10 is 8/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
7/21 = 7 × 10/21 × 10 = 70/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
2/10 = 2 × 21/10 × 21 = 42/210 - Add the two like fractions:
70/210 + 42/210 = 70 + 42/210 = 112/210 - 112/210 simplified gives 8/15
- So, 7/21 + 2/10 = 8/15
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