Add 18/72 and 21/7
1st number: 18/72, 2nd number: 3 0/7
18/72 + 21/7 is 13/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 7 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 7 × 72 = 504,
21/7 = 21 × 72/7 × 72 = 1512/504 - Add the two like fractions:
126/504 + 1512/504 = 126 + 1512/504 = 1638/504 - 1638/504 simplified gives 13/4
- So, 18/72 + 21/7 = 13/4
In mixed form: 31/4
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