Add 70/84 and 21/72
70/84 + 21/72 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 84 × 6 = 504,
70/84 = 70 × 6/84 × 6 = 420/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Add the two like fractions:
420/504 + 147/504 = 420 + 147/504 = 567/504 - 567/504 simplified gives 9/8
- So, 70/84 + 21/72 = 9/8
In mixed form: 11/8
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