Add 90/72 and 8/21
1st number: 1 18/72, 2nd number: 8/21
90/72 + 8/21 is 137/84.
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,
90/72 = 90 × 7/72 × 7 = 630/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
8/21 = 8 × 24/21 × 24 = 192/504 - Add the two like fractions:
630/504 + 192/504 = 630 + 192/504 = 822/504 - 822/504 simplified gives 137/84
- So, 90/72 + 8/21 = 137/84
In mixed form: 153/84
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