Add 40/15 and 30/21
1st number: 2 10/15, 2nd number: 1 9/21
40/15 + 30/21 is 86/21.
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,
40/15 = 40 × 7/15 × 7 = 280/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
30/21 = 30 × 5/21 × 5 = 150/105 - Add the two like fractions:
280/105 + 150/105 = 280 + 150/105 = 430/105 - 430/105 simplified gives 86/21
- So, 40/15 + 30/21 = 86/21
In mixed form: 42/21
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