If f(x) = x/2 – 1, what is the value of f(f(10))?

Question

If  f(x) = \frac{x}{2}– 1 , what is the value of  f(f(10)) ?

A. 0
B. 1
C. 2
D. 3
E. 4

Gladiator59 · Answer

f(x) = \frac{x}{2}– 1 
 f(10) = \frac{10}{2}– 1 
 f(10) = 4

f(f(10)) = f(4) = \frac{4}{2}– 1 
 f(4) = 1

Hence Option )B) is our bet.

Best,
Gladi

EgmatQuantExpert · Answer

Solution 
  Given:  
 • f(x) =  \frac{x}{2} - 1

To find:  
 • The value of f(f(10))

Approach and Working:   
 • f(10) =  \frac{10}{2} – 1 = 4 
• f(f(10)) = f(4) = \frac{4}{2} – 1 = 1

Hence, the correct answer is Option B

Answer: B

https://e-gmat.com/blogs/wp-content/uploads/2018/08/Free-Session-Algebra-e1533292089856.jpg

BrushMyQuant · Answer

Given that  f(x) = \frac{x}{2}– 1  and we need to find the value of  f(f(10)) ?

To find f(10) we need to compare what is inside ( ) in f(10) and f(x)

=> We need to substitute x with 10 in  f(x) = \frac{x}{2}– 1  to get the value of f(10)

=>  f(10) = \frac{10}{2}– 1  = 5 - 1 = 4

=> f(f(10)) = f(4) =  \frac{4}{2}– 1  = 2 - 1 = 1

So,  Answer will be B 
Hope it helps!

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