Add 18/21 and 21/70
18/21 + 21/70 is 81/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
18/21 = 18 × 10/21 × 10 = 180/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210 - Add the two like fractions:
180/210 + 63/210 = 180 + 63/210 = 243/210 - 243/210 simplified gives 81/70
- So, 18/21 + 21/70 = 81/70
In mixed form: 111/70
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