Add 30/72 and 40/21
1st number: 30/72, 2nd number: 1 19/21
30/72 + 40/21 is 65/28.
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,
30/72 = 30 × 7/72 × 7 = 210/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
40/21 = 40 × 24/21 × 24 = 960/504 - Add the two like fractions:
210/504 + 960/504 = 210 + 960/504 = 1170/504 - 1170/504 simplified gives 65/28
- So, 30/72 + 40/21 = 65/28
In mixed form: 29/28
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