Add 45/56 and 21/90
45/56 + 21/90 is 871/840.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 90 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 56 × 45 = 2520,
45/56 = 45 × 45/56 × 45 = 2025/2520 - Likewise, for the 2nd fraction, since 90 × 28 = 2520,
21/90 = 21 × 28/90 × 28 = 588/2520 - Add the two like fractions:
2025/2520 + 588/2520 = 2025 + 588/2520 = 2613/2520 - 2613/2520 simplified gives 871/840
- So, 45/56 + 21/90 = 871/840
In mixed form: 131/840
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