Add 56/70 and 21/90
56/70 + 21/90 is 31/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
56/70 = 56 × 9/70 × 9 = 504/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
504/630 + 147/630 = 504 + 147/630 = 651/630 - 651/630 simplified gives 31/30
- So, 56/70 + 21/90 = 31/30
In mixed form: 11/30
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