Add 21/63 and 28/40
21/63 + 28/40 is 31/30.
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,
21/63 = 21 × 40/63 × 40 = 840/2520 - Likewise, for the 2nd fraction, since 40 × 63 = 2520,
28/40 = 28 × 63/40 × 63 = 1764/2520 - Add the two like fractions:
840/2520 + 1764/2520 = 840 + 1764/2520 = 2604/2520 - 2604/2520 simplified gives 31/30
- So, 21/63 + 28/40 = 31/30
In mixed form: 11/30
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