High School

Calculate the sum of the fractions:

\frac{-7}{10} + \frac{13}{15} + \frac{27}{20}

Answer :

To calculate the sum of the fractions [tex]\frac{-7}{10} + \frac{13}{15} + \frac{27}{20}[/tex], we need to find a common denominator so that we can add them together.

  1. Determine the Least Common Denominator (LCD):

    • The denominators are 10, 15, and 20.
    • The least common multiple (LCM) of these numbers is 60.
  2. Convert each fraction to have the LCD as the denominator:

    • [tex]\frac{-7}{10}[/tex] becomes [tex]\frac{-7 \times 6}{10 \times 6} = \frac{-42}{60}[/tex].
    • [tex]\frac{13}{15}[/tex] becomes [tex]\frac{13 \times 4}{15 \times 4} = \frac{52}{60}[/tex].
    • [tex]\frac{27}{20}[/tex] becomes [tex]\frac{27 \times 3}{20 \times 3} = \frac{81}{60}[/tex].
  3. Add the fractions:

    • Now, add the numerators of the fractions since they have the same denominator:
      [tex]\frac{-42}{60} + \frac{52}{60} + \frac{81}{60} = \frac{-42 + 52 + 81}{60}[/tex]
    • Calculate the sum of the numerators:
      [tex]-42 + 52 + 81 = 91[/tex]
    • Therefore, the resulting fraction is:
      [tex]\frac{91}{60}[/tex]
  4. Simplify if necessary:

    • The fraction [tex]\frac{91}{60}[/tex] is already in its simplest form.

Therefore, the sum of the fractions is [tex]\frac{91}{60}[/tex].