Calculate the first term

Find $45\%$ of $800$ by multiplying $800$ by $\frac{45}{100}$.

$rac{45}{100} imes 800 = 360$

Calculate the second term

Find $25\%$ of $400$ which is one-fourth of $400$.

$rac{25}{100} imes 400 = 100$

Calculate the third term

Find $30\%$ of $200$ by multiplying $200$ by $\frac{30}{100}$.

$rac{30}{100} imes 200 = 60$

Evaluate the complete expression

Substitute the calculated values into the original expression: $360 + 100 - 60$.

$360 + 100 - 60 = 400$