Add 81/42 and 72/10
1st number: 1 39/42, 2nd number: 7 2/10
81/42 + 72/10 is 639/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
72/10 = 72 × 21/10 × 21 = 1512/210 - Add the two like fractions:
405/210 + 1512/210 = 405 + 1512/210 = 1917/210 - 1917/210 simplified gives 639/70
- So, 81/42 + 72/10 = 639/70
In mixed form: 99/70
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