Add 42/21 and 18/72
1st number: 2 0/21, 2nd number: 18/72
42/21 + 18/72 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
42/21 = 42 × 24/21 × 24 = 1008/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
18/72 = 18 × 7/72 × 7 = 126/504 - Add the two like fractions:
1008/504 + 126/504 = 1008 + 126/504 = 1134/504 - 1134/504 simplified gives 9/4
- So, 42/21 + 18/72 = 9/4
In mixed form: 21/4
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