Add 21/60 and 90/21
1st number: 21/60, 2nd number: 4 6/21
21/60 + 90/21 is 649/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
21/60 = 21 × 7/60 × 7 = 147/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
90/21 = 90 × 20/21 × 20 = 1800/420 - Add the two like fractions:
147/420 + 1800/420 = 147 + 1800/420 = 1947/420 - 1947/420 simplified gives 649/140
- So, 21/60 + 90/21 = 649/140
In mixed form: 489/140
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