Add 30/40 and 21/63
30/40 + 21/63 is 13/12.
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,
30/40 = 30 × 63/40 × 63 = 1890/2520 - Likewise, for the 2nd fraction, since 63 × 40 = 2520,
21/63 = 21 × 40/63 × 40 = 840/2520 - Add the two like fractions:
1890/2520 + 840/2520 = 1890 + 840/2520 = 2730/2520 - 2730/2520 simplified gives 13/12
- So, 30/40 + 21/63 = 13/12
In mixed form: 11/12
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