Add 12/21 and 90/72
1st number: 12/21, 2nd number: 1 18/72
12/21 + 90/72 is 51/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
12/21 = 12 × 24/21 × 24 = 288/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Add the two like fractions:
288/504 + 630/504 = 288 + 630/504 = 918/504 - 918/504 simplified gives 51/28
- So, 12/21 + 90/72 = 51/28
In mixed form: 123/28
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