Add 12/16 and 42/21
1st number: 12/16, 2nd number: 2 0/21
12/16 + 42/21 is 11/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 21 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 16 × 21 = 336,
12/16 = 12 × 21/16 × 21 = 252/336 - Likewise, for the 2nd fraction, since 21 × 16 = 336,
42/21 = 42 × 16/21 × 16 = 672/336 - Add the two like fractions:
252/336 + 672/336 = 252 + 672/336 = 924/336 - 924/336 simplified gives 11/4
- So, 12/16 + 42/21 = 11/4
In mixed form: 23/4
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