(0.75ast 40)/(0.4ast 0.60)(6-0.4ast 2-4)-(4)/(0.4)

To solve the expression, we need to follow the order of operations (PEMDAS/BODMAS). Let's break it down step by step:<br /><br />Given expression:<br />\[<br />\frac{0.75 \times 40}{0.4 \times 0.60} (6 - 0.4 \times 2 - 4) - \frac{4}{0.4}<br />\]<br /><br />1. **Calculate the numerator and denominator of the first fraction:**<br /> \[<br /> 0.75 \times 40 = 30<br /> \]<br /> \[<br /> 0.4 \times 0.60 = 0.24<br /> \]<br /><br />2. **Divide the results:**<br /> \[<br /> \frac{30}{0.24} = 125<br /> \]<br /><br />3. **Simplify the expression inside the parentheses:**<br /> \[<br /> 6 - 0.4 \times 2 - 4<br /> \]<br /> \[<br /> 0.4 \times 2 = 0.8<br /> \]<br /> \[<br /> 6 - 0.8 - 4 = 1.2<br /> \]<br /><br />4. **Multiply the result by the fraction:**<br /> \[<br /> 125 \times 1.2 = 150<br /> \]<br /><br />5. **Calculate the second fraction:**<br /> \[<br /> \frac{4}{0.4} = 10<br /> \]<br /><br />6. **Subtract the second fraction from the first result:**<br /> \[<br /> 150 - 10 = 140<br /> \]<br /><br />So, the final answer is:<br />\[<br />140<br />\]