Add 42/8 and 72/21
1st number: 5 2/8, 2nd number: 3 9/21
42/8 + 72/21 is 243/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
42/8 = 42 × 21/8 × 21 = 882/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
72/21 = 72 × 8/21 × 8 = 576/168 - Add the two like fractions:
882/168 + 576/168 = 882 + 576/168 = 1458/168 - 1458/168 simplified gives 243/28
- So, 42/8 + 72/21 = 243/28
In mixed form: 819/28
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