Add 4/40 and 12/21
4/40 + 12/21 is 47/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
4/40 = 4 × 21/40 × 21 = 84/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
12/21 = 12 × 40/21 × 40 = 480/840 - Add the two like fractions:
84/840 + 480/840 = 84 + 480/840 = 564/840 - 564/840 simplified gives 47/70
- So, 4/40 + 12/21 = 47/70
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