1. (-11/4-3/8)x160=-22/8-3/8)x160=-25/8x160=-25x20=-500
2 (3/4+19/8)X25,8=25,8x25,8=665,64
3. 728²-26²:754=(728-26)(728+26):754=(702)(754):754=702
4. 86/100x20/43=2/5
5 42/100x10/3=14/10=1,4
6. 1/3x0,99+2=0,33+2=2,33
7 (3,9-2,4)х 8,2=1,5х8,2=12,3
8 29/7:29/28=29/7x28/29=4
9 21/24-34/24 x12/5=-13/24x12/5=26/5=5,2
10 9,5+8,9/2,3=18,4/2,3=8
11 25/17:4/17=25/17 x17/4=25/4=6,25