Add 21/70 and 18/28
21/70 + 18/28 is 33/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
18/28 = 18 × 5/28 × 5 = 90/140 - Add the two like fractions:
42/140 + 90/140 = 42 + 90/140 = 132/140 - 132/140 simplified gives 33/35
- So, 21/70 + 18/28 = 33/35
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