Add 42/70 and 18/72
42/70 + 18/72 is 17/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 70 × 36 = 2520,
42/70 = 42 × 36/70 × 36 = 1512/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
18/72 = 18 × 35/72 × 35 = 630/2520 - Add the two like fractions:
1512/2520 + 630/2520 = 1512 + 630/2520 = 2142/2520 - 2142/2520 simplified gives 17/20
- So, 42/70 + 18/72 = 17/20
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