Question

Subtract `2/7 - 5/21` from the sum of `3/4, 5/7  "and"  7/12`

Answer 1

`(3/4 + 5/7 + 7/12) - (2/7 - 5/21)`

The least common denominator (LCD) of 7 and 21 is 21.

Rewrite the fractions: `2/7 = 6/21`

`2/7 - 5/21 = 6/21-5/21 = 1/21`

The least common denominator (LCD) of 4, 7, and 12 is 84.

`3/4 = 63/84, 5/7 = 60/84, 7/12 = 49/84`

Add: `3/4+5/7+7/12`

`= 63/84 + 60/84+49/84`

`(63+60+49)/84`

`= 172/84`

`172/84 = 43/21`

Since the denominators are the same, subtract the numerators:

`43/21-1/21=(43-1)/21 = 42/21`

`42/21`

= 2