I need to find the LCD of fractions 3/4 + 6/7 and how to solve

Question

I need to find the LCD of fractions 3/4 + 6/7 and how to solve

in progress 0
Harper 2 weeks 2021-11-25T09:57:58+00:00 1 Answer 0

Answers ( )

    0
    2021-11-25T09:59:55+00:00

    The least common denominator of two fraction is the least common multiple of the two denominator.

    The least common multiple of 4 and 7 is their product 28, because 4 and 7 have no common factor.

    Now, we need to manipulate both fractions so that they have denominator 28. Recalling that you can multiply numerator and denominator of a fraction by the same number without affecting its value, we have

    \dfrac{3}{4}=\dfrac{3\cdot 7}{4\cdot 7}=\dfrac{21}{28},\quad \dfrac{6}{7}=\dfrac{6\cdot 4}{7\cdot 4}=\dfrac{24}{28}

    So, the sum becomes

    \dfrac{3}{4}+\dfrac{6}{7}=\dfrac{21}{28}+\dfrac{24}{28}=\dfrac{21+24}{28}=\dfrac{45}{28}

    In fact, when two fractions have the same denominator, you can directly sum their numerators.

Leave an answer

Browse
Browse

27:3+15-4x7+3-1=? ( )