Add 42/70 and 72/21
1st number: 42/70, 2nd number: 3 9/21
42/70 + 72/21 is 141/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
42/70 = 42 × 3/70 × 3 = 126/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
72/21 = 72 × 10/21 × 10 = 720/210 - Add the two like fractions:
126/210 + 720/210 = 126 + 720/210 = 846/210 - 846/210 simplified gives 141/35
- So, 42/70 + 72/21 = 141/35
In mixed form: 41/35
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