Add 21/40 and 90/63
1st number: 21/40, 2nd number: 1 27/63
21/40 + 90/63 is 547/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 63 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 40 × 63 = 2520,
21/40 = 21 × 63/40 × 63 = 1323/2520 - Likewise, for the 2nd fraction, since 63 × 40 = 2520,
90/63 = 90 × 40/63 × 40 = 3600/2520 - Add the two like fractions:
1323/2520 + 3600/2520 = 1323 + 3600/2520 = 4923/2520 - 4923/2520 simplified gives 547/280
- So, 21/40 + 90/63 = 547/280
In mixed form: 1267/280
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