Answer: 648 pull-ups
Step-by-step explanation:
Given
Max take 5.5 minutes to do 60 Pull-ups with a break in between
Similarly, it took 8 minutes for 120 pull-ups
Suppose the time taken for a single pull-up and break is x and y minutes
So, it can be written
[tex]\Rightarrow 60x+y=5.5\quad \ldots(i)\\\Rightarrow 120x+y=8\quad \ldots(ii)\\\\\text{Solve (i) and (ii) we get}\\\\x=\dfrac{2.5}{60}\ min \ or\ \ 2.5\ s\\\\y=3\ min[/tex]
Now, suppose max perform at this rate, and the total pull-ups are P in 30 minutes
[tex]\therefore P\times \dfrac{2.5}{60}+3=30\\\\\Rightarrow P\times \dfrac{2.5}{60}=27\\\\\Rightarrow P=648\ \text{Pull-ups}[/tex]
