In a vce external examination, 20% of the students failed physics, 15% of the students failed biology and 12% of the students failed both physics and biology. a student is selected at random. a) if she or he failed biology, what is the probability that she or he also failed physics? b) what is the probability that she or he failed physics or biology?

answer: solve 5\cdot 2^x=2405⋅2  

x

=2405, dot, 2, start superscript, x, end superscript, equals, 240.

solution

to solve for xxx, we must first isolate the exponential part. to do this, divide both sides by 555 as shown below. we do not multiply the 555 and the 222 as this goes against the order of operations!

\begin{aligned} 5\cdot 2^x& =240 2^x& =48 \\ \end{aligned}  

5⋅2  

x

2  

x

​    

=240

=48

​

step-by-step explanation: