Add 21/40 and 84/63
1st number: 21/40, 2nd number: 1 21/63
21/40 + 84/63 is 223/120.
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,
84/63 = 84 × 40/63 × 40 = 3360/2520 - Add the two like fractions:
1323/2520 + 3360/2520 = 1323 + 3360/2520 = 4683/2520 - 4683/2520 simplified gives 223/120
- So, 21/40 + 84/63 = 223/120
In mixed form: 1103/120
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