Add 21/25 and 18/81
21/25 + 18/81 is 239/225.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 81 is 2025
Next, find the equivalent fraction of both fractional numbers with denominator 2025 - For the 1st fraction, since 25 × 81 = 2025,
21/25 = 21 × 81/25 × 81 = 1701/2025 - Likewise, for the 2nd fraction, since 81 × 25 = 2025,
18/81 = 18 × 25/81 × 25 = 450/2025 - Add the two like fractions:
1701/2025 + 450/2025 = 1701 + 450/2025 = 2151/2025 - 2151/2025 simplified gives 239/225
- So, 21/25 + 18/81 = 239/225
In mixed form: 114/225
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