If the decimal part of 5 is x, what is the decimal part of 45?

Question

If the decimal part of  \sqrt{5}  is  x , what is the decimal part of  \sqrt{45} ?

A.  3x - 2  
 
B.  3x - 1 
 
C.  3x 
 
D.  3x + 1  
 
E.  3x + 2

ArunSharma12 · Answer

\sqrt{5} = 2 + x 
 \sqrt{45}= 3\sqrt{5} = 3(x+2)= 3x + 6 
decimal part = 3x
Ans: C

MathRevolution · Answer

=>

Since  2 < √5 < 3,  we have  x = √5 - 2.

Since  6 < √45 < 7 , the decimal part of  √45  is  √45 – 6 = 3√5 – 6 = 3(√5 - 2) = 3x.

Therefore, C is the answer.
Answer: C

Neghineh · Answer

Could you break this down for me and explain?

abhimanyujain1711 · Answer

i think the question could have been better phrased. it's slightly ambiguous.

decimal part means just the part after the decimal and not the entire part.

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