Add 21/48 and 72/90
21/48 + 72/90 is 99/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 48 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 48 × 15 = 720,
21/48 = 21 × 15/48 × 15 = 315/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
72/90 = 72 × 8/90 × 8 = 576/720 - Add the two like fractions:
315/720 + 576/720 = 315 + 576/720 = 891/720 - 891/720 simplified gives 99/80
- So, 21/48 + 72/90 = 99/80
In mixed form: 119/80
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