Add 90/72 and 21/84
1st number: 1 18/72, 2nd number: 21/84
90/72 + 21/84 is 3/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 84 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Likewise, for the 2nd fraction, since 84 × 6 = 504,
21/84 = 21 × 6/84 × 6 = 126/504 - Add the two like fractions:
630/504 + 126/504 = 630 + 126/504 = 756/504 - 756/504 simplified gives 3/2
- So, 90/72 + 21/84 = 3/2
In mixed form: 11/2
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