Add 70/15 and 45/21
1st number: 4 10/15, 2nd number: 2 3/21
70/15 + 45/21 is 143/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
70/15 = 70 × 7/15 × 7 = 490/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
45/21 = 45 × 5/21 × 5 = 225/105 - Add the two like fractions:
490/105 + 225/105 = 490 + 225/105 = 715/105 - 715/105 simplified gives 143/21
- So, 70/15 + 45/21 = 143/21
In mixed form: 617/21
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