Add 18/21 and 40/48
18/21 + 40/48 is 71/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 48 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 21 × 16 = 336,
18/21 = 18 × 16/21 × 16 = 288/336 - Likewise, for the 2nd fraction, since 48 × 7 = 336,
40/48 = 40 × 7/48 × 7 = 280/336 - Add the two like fractions:
288/336 + 280/336 = 288 + 280/336 = 568/336 - 568/336 simplified gives 71/42
- So, 18/21 + 40/48 = 71/42
In mixed form: 129/42
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