Add 72/10 and 21/42
1st number: 7 2/10, 2nd number: 21/42
72/10 + 21/42 is 77/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
72/10 = 72 × 21/10 × 21 = 1512/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Add the two like fractions:
1512/210 + 105/210 = 1512 + 105/210 = 1617/210 - 1617/210 simplified gives 77/10
- So, 72/10 + 21/42 = 77/10
In mixed form: 77/10
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