Question

Which of the following is the prime factored form of the lowest common denominator 6/7 + 5/6 ?

a. 2 x 7
b. 2 x 3 x 3 x4
c.6 x7
d. 2 x 3 x7

Answer 1

d

Explanation:

we are looking for the LCD ( lowest common denominator ) for 6 and 7

7 is prime

the factors of 6 are 1, 2, 3, 6

of which 2 and 3 are prime

then the LCD of 6 and 7 is 2 × 3 × 7 = 42