1170.

[tex](3 \frac{3}{4} \div 1 \frac{1}{4} - 0.75 ) \div 1 \frac{1}{2} + 0.75 =2.25 \\ 1) \: 3 \frac{3}{4} \div 1 \frac{1}{4} = \frac{15 \times 4}{4 \times 5} = 3 \\ 2) \: 3 - 0.75 = 2.25 \\ 3) \: 2.25 \div 1 \frac{1}{2} = \frac{9 \times 2}{4 \times 3} = \frac{3}{2} = 1.5 \\ 4) \: 1.5 + 0.75 = 2.25[/tex]