Answer :

[tex]15 \frac{1}{4} +1 \frac{1}{2} + \frac{3}{20} =15 \frac{5}{20} +1 \frac{10}{20} + \frac{3}{20}=16 \frac{18}{20} =16 \frac{9}{10} =16.9[/tex]
15  1/4  + 1  1/2   + 3/20

= 61/4 + 1.5 + 0.15

= 15.25 + 1.65

= 16.90
Thus, the answer is 16.90