Add 15/40 and 21/7
1st number: 15/40, 2nd number: 3 0/7
15/40 + 21/7 is 27/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
15/40 = 15 × 7/40 × 7 = 105/280 - Likewise, for the 2nd fraction, since 7 × 40 = 280,
21/7 = 21 × 40/7 × 40 = 840/280 - Add the two like fractions:
105/280 + 840/280 = 105 + 840/280 = 945/280 - 945/280 simplified gives 27/8
- So, 15/40 + 21/7 = 27/8
In mixed form: 33/8
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