(11/12+11/20)*15/8

To solve the expression \((\frac{11}{12} + \frac{11}{20}) \times \frac{15}{8}\), we follow these steps:

1. Find a common denominator for the fractions \(\frac{11}{12}\) and \(\frac{11}{20}\).

   • The least common multiple (LCM) of 12 and 20 is 60.

   Convert each fraction:

   • \(\frac{11}{12} = \frac{11 \times 5}{12 \times 5} = \frac{55}{60}\)
   • \(\frac{11}{20} = \frac{11 \times 3}{20 \times 3} = \frac{33}{60}\)

2. Add the fractions: \[ \frac{55}{60} + \frac{33}{60} = \frac{55 + 33}{60} = \frac{88}{60} \]

3. Simplify \(\frac{88}{60}\): \[ \frac{88 \div 4}{60 \div 4} = \frac{22}{15} \]

4. Multiply by \(\frac{15}{8}\): \[ \frac{22}{15} \times \frac{15}{8} \] The 15's cancel out: \[ = \frac{22}{8} \]

5. Simplify \(\frac{22}{8}\): \[ \frac{22 \div 2}{8 \div 2} = \frac{11}{4} \]

Thus, the final answer is: \[ \frac{11}{4} \]