Add 42/70 and 21/4
1st number: 42/70, 2nd number: 5 1/4
42/70 + 21/4 is 117/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 4 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
42/70 = 42 × 2/70 × 2 = 84/140 - Likewise, for the 2nd fraction, since 4 × 35 = 140,
21/4 = 21 × 35/4 × 35 = 735/140 - Add the two like fractions:
84/140 + 735/140 = 84 + 735/140 = 819/140 - 819/140 simplified gives 117/20
- So, 42/70 + 21/4 = 117/20
In mixed form: 517/20
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