Add 72/30 and 42/21
1st number: 2 12/30, 2nd number: 2 0/21
72/30 + 42/21 is 22/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
72/30 = 72 × 7/30 × 7 = 504/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210 - Add the two like fractions:
504/210 + 420/210 = 504 + 420/210 = 924/210 - 924/210 simplified gives 22/5
- So, 72/30 + 42/21 = 22/5
In mixed form: 42/5
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