1/2 divided by -2/3 times 3/4 -4/5

To divide a fraction, invert the fraction and multiply so the problem is 1/2 * -3/2 * 3/4 = -9/16. Now add - 9/16 - 4/5. First get a common denominator of 80 and change each fraction which will be - 45/80 - 64/80 which equals - 109/80. Reduce this to - 1 and 29/80.