Add 8/21 and 12/40
8/21 + 12/40 is 143/210.
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,
8/21 = 8 × 40/21 × 40 = 320/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
12/40 = 12 × 21/40 × 21 = 252/840 - Add the two like fractions:
320/840 + 252/840 = 320 + 252/840 = 572/840 - 572/840 simplified gives 143/210
- So, 8/21 + 12/40 = 143/210
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