Answer:
50
Explanation:
The mechanical advantage of a machine is given by
where
is the output force
is the input force
For the crowbar in this problem,
is the force in input applied by the worker
is the force that the machine must apply in output to overcome the resistance of the window and to open it
Substituting into the equation, we find
The decimal point is placed after two digits starting from the end. For each decimal place, we can write the number divided by 100.
21.12 can be written as .
Divide the numerator and denominator by 2:
The numerator and denominator can be divided by 2 again:
There is no other common factor between numerator and denominator other than 1. Hence, it is the reduced form.