Answer:
The value of z-y is 14x/5
Explanation:
The value of x decreased by 80% is → x - x * 80/100 = x - x*4/5 = x/5. This also equals to y → y = x/5. (1)
The value of x increased by 200% is → x + x * 200/100 = x + 2x = 3x. This also equals to z → z = 3x. (2)
If you substitute the values from the equation 1 and equation 2, the value of z - y → (3x) - (x/5) = 14x/5