Verified Answer :

  • Separate the expression into integer and fractional parts: \((5 + 2) + (\frac{3}{4} + \frac{3}{5})\).
  • Add the integer parts to get 7.
  • Find a common denominator of 20 to add the fractions: \(\frac{15}{20} + \frac{12}{20} = \frac{27}{20} = 1 \frac{7}{20}\).
  • Combine the results: \(7 + 1 \frac{7}{20} = 8 \frac{7}{20}\).
  • The final result is \(\boxed{8 \frac{7}{20}}\).

Explanation

  1. Analysis of the problem

We need to calculate the sum of two mixed numbers, \(5 \frac{3}{4}\) and \(2 \frac{3}{5}\). A mixed number is a sum of an integer and a proper fraction. The expression can be written as \((5 + \frac{3}{4}) + (2 + \frac{3}{5})\). To solve this, we can add the integer parts and the fractional parts separately.

  1. Grouping and Common Denominators

First, group the integer parts: \(5 + 2 = 7\). Next, group the fractional parts: \(\frac{3}{4} + \frac{3}{5}\). To add these two fractions, we must find a common denominator. The least common multiple of 4 and 5 is 20. We convert each fraction:
\[\frac{3}{4} = \frac{3 \times 5}{4 \times 5} = \frac{15}{20}\]
\[\frac{3}{5} = \frac{3 \times 4}{5 \times 4} = \frac{12}{20}\]
Summing these gives: \(\frac{15}{20} + \frac{12}{20} = \frac{27}{20}\).

  1. Final Calculation and Result

Now, convert the improper fraction \(\frac{27}{20}\) back to a mixed number. Since 20 goes into 27 one time with a remainder of 7, we have \(\frac{27}{20} = 1 \frac{7}{20}\). Finally, add this to the sum of the integer parts: \(7 + 1 \frac{7}{20} = 8 \frac{7}{20}\). Alternatively, as an improper fraction, this is \(8 \times \frac{20}{20} + \frac{7}{20} = \frac{160+7}{20} = \frac{167}{20}\). The result is \(\boxed{8 \frac{7}{20}}\).

Examples

Understanding how to work with mixed numbers is essential for real-world scenarios such as construction or cooking. For example, if you are building a shelf and need two boards of length \(5 \frac{3}{4}\) feet and \(2 \frac{3}{5}\) feet, adding these values helps you calculate the total length of wood required for your project: \(5 \frac{3}{4} + 2 \frac{3}{5} = 8 \frac{7}{20}\) feet. This skill ensures accuracy in measurements and material procurement.