Add 21/35 and 42/80
21/35 + 42/80 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 35 × 16 = 560,
21/35 = 21 × 16/35 × 16 = 336/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
42/80 = 42 × 7/80 × 7 = 294/560 - Add the two like fractions:
336/560 + 294/560 = 336 + 294/560 = 630/560 - 630/560 simplified gives 9/8
- So, 21/35 + 42/80 = 9/8
In mixed form: 11/8
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