Hi this not a answer but this can help you use photo math
So how many does he have left
25-16=9
9 floors left
the want a percentage so 9 out of 25
percent is out of 100
a hack for this specific problem is that 25 is exactly 1/4 of 100 so
9/25 times 1=the same thing so
9/25 times 4/4 (simplifies to 1)=(9 times 4)/(25 times 4)
36/100
this is out of 100 so
36%
of course there is a legit way of solving this problem but this is a hack (this works for factors of 100 like 2,4,5,10,20,25,50)
The expression "f(x)" means "plug a value for x into a formula f "; the expression does not mean "multiply f and x"! Don't embarrass yourself by pronouncing or thinking of "f(x)" as being "f times x". In notation, the "x" in "f(x)" is called "the argument of the function", or just "the argument".
