Add 20/40 and 70/81
20/40 + 70/81 is 221/162.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 81 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 40 × 81 = 3240,
20/40 = 20 × 81/40 × 81 = 1620/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
70/81 = 70 × 40/81 × 40 = 2800/3240 - Add the two like fractions:
1620/3240 + 2800/3240 = 1620 + 2800/3240 = 4420/3240 - 4420/3240 simplified gives 221/162
- So, 20/40 + 70/81 = 221/162
In mixed form: 159/162
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