Add 21/28 and 45/70
21/28 + 45/70 is 39/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 70 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
45/70 = 45 × 2/70 × 2 = 90/140 - Add the two like fractions:
105/140 + 90/140 = 105 + 90/140 = 195/140 - 195/140 simplified gives 39/28
- So, 21/28 + 45/70 = 39/28
In mixed form: 111/28
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