Add 30/20 and 90/21
1st number: 1 10/20, 2nd number: 4 6/21
30/20 + 90/21 is 81/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
30/20 = 30 × 21/20 × 21 = 630/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
90/21 = 90 × 20/21 × 20 = 1800/420 - Add the two like fractions:
630/420 + 1800/420 = 630 + 1800/420 = 2430/420 - 2430/420 simplified gives 81/14
- So, 30/20 + 90/21 = 81/14
In mixed form: 511/14
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