Add 18/72 and 16/21
18/72 + 16/21 is 85/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
18/72 = 18 × 7/72 × 7 = 126/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
16/21 = 16 × 24/21 × 24 = 384/504 - Add the two like fractions:
126/504 + 384/504 = 126 + 384/504 = 510/504 - 510/504 simplified gives 85/84
- So, 18/72 + 16/21 = 85/84
In mixed form: 11/84
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