Add 21/15 and 90/56
1st number: 1 6/15, 2nd number: 1 34/56
21/15 + 90/56 is 421/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 56 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 15 × 56 = 840,
21/15 = 21 × 56/15 × 56 = 1176/840 - Likewise, for the 2nd fraction, since 56 × 15 = 840,
90/56 = 90 × 15/56 × 15 = 1350/840 - Add the two like fractions:
1176/840 + 1350/840 = 1176 + 1350/840 = 2526/840 - 2526/840 simplified gives 421/140
- So, 21/15 + 90/56 = 421/140
In mixed form: 31/140
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