Add 30/63 and 21/40
30/63 + 21/40 is 841/840.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 40 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 63 × 40 = 2520,
30/63 = 30 × 40/63 × 40 = 1200/2520 - Likewise, for the 2nd fraction, since 40 × 63 = 2520,
21/40 = 21 × 63/40 × 63 = 1323/2520 - Add the two like fractions:
1200/2520 + 1323/2520 = 1200 + 1323/2520 = 2523/2520 - 2523/2520 simplified gives 841/840
- So, 30/63 + 21/40 = 841/840
In mixed form: 11/840
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