Add 18/72 and 40/21
1st number: 18/72, 2nd number: 1 19/21
18/72 + 40/21 is 181/84.
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,
40/21 = 40 × 24/21 × 24 = 960/504 - Add the two like fractions:
126/504 + 960/504 = 126 + 960/504 = 1086/504 - 1086/504 simplified gives 181/84
- So, 18/72 + 40/21 = 181/84
In mixed form: 213/84
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