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