Add 5/21 and 30/40
5/21 + 30/40 is 83/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
5/21 = 5 × 40/21 × 40 = 200/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Add the two like fractions:
200/840 + 630/840 = 200 + 630/840 = 830/840 - 830/840 simplified gives 83/84
- So, 5/21 + 30/40 = 83/84
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