To solve the equation \( 86.4 : (35.5 - 7x) = 16 \), we can begin by simplifying and isolating \( x \).
Rewrite the expression using multiplication for clarity: \[ \frac{86.4}{35.5 - 7x} = 16 \]
To eliminate the fraction, multiply both sides by \( 35.5 - 7x \): \[ 86.4 = 16 \times (35.5 - 7x) \]
Distributing on the right side: \[ 86.4 = 568 - 112x \]
Now, isolate \( x \) by moving \( 112x \) to the left side and \( 86.4 \) to the right: \[ 112x = 568 - 86.4 \]
Calculate \( 568 - 86.4 \): \[ 568 - 86.4 = 481.6 \] So, we have: \[ 112x = 481.6 \]
Divide both sides by 112 to solve for \( x \): \[ x = \frac{481.6}{112} \]
Calculate the division: \[ x = 4.3 \]
Thus, the solution is: \[ x = 4.3 \]