Add 54/20 and 90/21
1st number: 2 14/20, 2nd number: 4 6/21
54/20 + 90/21 is 489/70.
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,
54/20 = 54 × 21/20 × 21 = 1134/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
90/21 = 90 × 20/21 × 20 = 1800/420 - Add the two like fractions:
1134/420 + 1800/420 = 1134 + 1800/420 = 2934/420 - 2934/420 simplified gives 489/70
- So, 54/20 + 90/21 = 489/70
In mixed form: 669/70
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