Add 21/30 and 42/48
21/30 + 42/48 is 63/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 48 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 30 × 8 = 240,
21/30 = 21 × 8/30 × 8 = 168/240 - Likewise, for the 2nd fraction, since 48 × 5 = 240,
42/48 = 42 × 5/48 × 5 = 210/240 - Add the two like fractions:
168/240 + 210/240 = 168 + 210/240 = 378/240 - 378/240 simplified gives 63/40
- So, 21/30 + 42/48 = 63/40
In mixed form: 123/40
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