We are given the following information:
First, simplify the given equation:
$\frac{1}{2}P = \frac{3}{5}Q + 12$
Multiply the entire equation by 10 to eliminate fractions:
5P = 6Q + 120
Thus, we have our first equation:
Equation 1: 5P = 6Q + 120
Now, from the second condition P + Q = 156, we can express P as:
Equation 2: P = 156 - Q
Substitute Equation 2 into Equation 1:
5(156 - Q) = 6Q + 120
Simplify:
Solve for Q:
780 - 5Q = 6Q + 120
780 - 120 = 6Q + 5Q
660 = 11Q
$Q = \frac{660}{11} = 60$
Now, substitute Q = 60 back into Equation 2 to find P:
P = 156 - 60 = 96
Finally, find 75% of P:
75% of P = $\frac{75}{100} \times 96 = 72$
Thus, the correct answer is (b) 72.
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