Add 21/70 and 18/80
21/70 + 18/80 is 21/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 70 × 8 = 560,
21/70 = 21 × 8/70 × 8 = 168/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
18/80 = 18 × 7/80 × 7 = 126/560 - Add the two like fractions:
168/560 + 126/560 = 168 + 126/560 = 294/560 - 294/560 simplified gives 21/40
- So, 21/70 + 18/80 = 21/40
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