Add 72/21 and 42/9
1st number: 3 9/21, 2nd number: 4 6/9
72/21 + 42/9 is 170/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
72/21 = 72 × 3/21 × 3 = 216/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
42/9 = 42 × 7/9 × 7 = 294/63 - Add the two like fractions:
216/63 + 294/63 = 216 + 294/63 = 510/63 - 510/63 simplified gives 170/21
- So, 72/21 + 42/9 = 170/21
In mixed form: 82/21
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