Add 21/8 and 42/70
1st number: 2 5/8, 2nd number: 42/70
21/8 + 42/70 is 129/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 8 × 35 = 280,
21/8 = 21 × 35/8 × 35 = 735/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
42/70 = 42 × 4/70 × 4 = 168/280 - Add the two like fractions:
735/280 + 168/280 = 735 + 168/280 = 903/280 - 903/280 simplified gives 129/40
- So, 21/8 + 42/70 = 129/40
In mixed form: 39/40
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