Add 21/70 and 20/21
21/70 + 20/21 is 263/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210 - Add the two like fractions:
63/210 + 200/210 = 63 + 200/210 = 263/210 - So, 21/70 + 20/21 = 263/210
In mixed form: 153/210
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