Add 4/20 and 70/81
4/20 + 70/81 is 431/405.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
4/20 = 4 × 81/20 × 81 = 324/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
70/81 = 70 × 20/81 × 20 = 1400/1620 - Add the two like fractions:
324/1620 + 1400/1620 = 324 + 1400/1620 = 1724/1620 - 1724/1620 simplified gives 431/405
- So, 4/20 + 70/81 = 431/405
In mixed form: 126/405
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