



 
Hi Kathy, I'm going to illustrate the procedure by doing a similar question \[3 \frac25 + 2 \frac38.\] First of all $3 = \large \frac{3 \times 5}{5} = \frac{15}{5}.$ Similarly $2 = \large \frac{16}{8}$ and hence \[3 \frac25 + 2 \frac38\ = \frac{15}{5} + \frac25 + \frac{16}{8} + \frac38\ = \frac{17}{5} + \frac{19}{8}.\] To add $\large \frac{17}{5}$ and $\large \frac{19}{8}$ I ned the two fractions to have a common denominator. I can find a common denominator by multiplying the two denominators and hence $5 \times 8 = 40$ is a common denominator. Thus \[ \frac{17}{5} + \frac{19}{8} = \frac{17 \times 8}{5 \times 8} + \frac{19 \times 5}{8 \times 5} = \frac{136}{40} + \frac{95}{40} = \frac{231}{40}. \] Now try your problems,  


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