Add 42/70 and 90/12
1st number: 42/70, 2nd number: 7 6/12
42/70 + 90/12 is 81/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 12 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
42/70 = 42 × 6/70 × 6 = 252/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
90/12 = 90 × 35/12 × 35 = 3150/420 - Add the two like fractions:
252/420 + 3150/420 = 252 + 3150/420 = 3402/420 - 3402/420 simplified gives 81/10
- So, 42/70 + 90/12 = 81/10
In mixed form: 81/10
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