Add 84/70 and 21/28
1st number: 1 14/70, 2nd number: 21/28
84/70 + 21/28 is 39/20.
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,
84/70 = 84 × 2/70 × 2 = 168/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Add the two like fractions:
168/140 + 105/140 = 168 + 105/140 = 273/140 - 273/140 simplified gives 39/20
- So, 84/70 + 21/28 = 39/20
In mixed form: 119/20
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