Add 21/4 and 90/72
1st number: 5 1/4, 2nd number: 1 18/72
21/4 + 90/72 is 13/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 4 × 18 = 72,
21/4 = 21 × 18/4 × 18 = 378/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
90/72 = 90 × 1/72 × 1 = 90/72 - Add the two like fractions:
378/72 + 90/72 = 378 + 90/72 = 468/72 - 468/72 simplified gives 13/2
- So, 21/4 + 90/72 = 13/2
In mixed form: 61/2
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