Add 70/20 and 21/28
1st number: 3 10/20, 2nd number: 21/28
70/20 + 21/28 is 17/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
70/20 = 70 × 7/20 × 7 = 490/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Add the two like fractions:
490/140 + 105/140 = 490 + 105/140 = 595/140 - 595/140 simplified gives 17/4
- So, 70/20 + 21/28 = 17/4
In mixed form: 41/4
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