The problem has missing information. But, i'll try to answer it.
1.5% should be converted into a decimal number before it can be added to 0.50P.
1.5% / 100% = 0.015
0.015 + 0.5P = 0
0.5P = -0.015
0.5P / 0.5 = -0.015/0.5
P = -0.03
To check:
0.015 + 0.5(-0.03) = 0
0.015 - 0.015 = 0
0 = 0
Since no information about the number of people in the squad is given, let us assume that the squad is composed of 30 people, So, P = 30
0.015 + (0.5*30) = 0.015 + 15 = 15.015