Explanation

1. Convert all fractions to a common denominator (8):

   • $\frac{3}{4}=\frac{6}{8}$

   • $\frac{5}{8}=\frac{5}{8}$

   • $\frac{1}{2}=\frac{4}{8}$

2. Perform the calculation:

   • $\frac{6}{8}+\frac{5}{8}-\frac{4}{8}=\frac{7}{8}$

3. Convert $\frac{7}{8}$ to decimal:

   • $\frac{7}{8}=0.875\approx 0.87$