Add 21/45 and 81/56
1st number: 21/45, 2nd number: 1 25/56
21/45 + 81/56 is 1607/840.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 56 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 45 × 56 = 2520,
21/45 = 21 × 56/45 × 56 = 1176/2520 - Likewise, for the 2nd fraction, since 56 × 45 = 2520,
81/56 = 81 × 45/56 × 45 = 3645/2520 - Add the two like fractions:
1176/2520 + 3645/2520 = 1176 + 3645/2520 = 4821/2520 - 4821/2520 simplified gives 1607/840
- So, 21/45 + 81/56 = 1607/840
In mixed form: 1767/840
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