Add 15/72 and 90/21
1st number: 15/72, 2nd number: 4 6/21
15/72 + 90/21 is 755/168.
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,
15/72 = 15 × 7/72 × 7 = 105/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
90/21 = 90 × 24/21 × 24 = 2160/504 - Add the two like fractions:
105/504 + 2160/504 = 105 + 2160/504 = 2265/504 - 2265/504 simplified gives 755/168
- So, 15/72 + 90/21 = 755/168
In mixed form: 483/168
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