Add 12/90 and 21/40
12/90 + 21/40 is 79/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
12/90 = 12 × 4/90 × 4 = 48/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
48/360 + 189/360 = 48 + 189/360 = 237/360 - 237/360 simplified gives 79/120
- So, 12/90 + 21/40 = 79/120
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