One integer will be randomly selected from the integers 11 to 60, incl

Question

One integer will be randomly selected from the integers 11 to 60, inclusive. What is the probability that the selected integer will be a perfect square or a perfect cube?

(A) 0.1
(B) 0.125
(C) 0.16
(D) 0.5
(E) 0.9

vaibhav1221 · Answer

5/48 = 0.10xx

Should be A

chetan2u · Answer

1) check for squares :-
3^2=9 and 8^2=64
so 4^2, 5^2, 6^2 and 7^2 will all give us a perfect square

2) now for cubes
2^3=8, 3^3=27 and 4^3=64
so only one 3^3

total 4+1=5 out of 60-11+1=50 integers

probability = 5/50 = 1/10 =0.1

A

chetan2u · Answer

5/48 is not 0.1...
since 11 and 60 are inclusive it will be 5/50

vaibhav1221 · Answer

My bad, made a silly calculation error to get max outcomes as 48. Plus i did not divide 5/48 any further to get 0.104. Thanks for pointing it out.

Regards,
V

KSBGC · Answer

Integer Range : 11 -60. Total no. of Integers = 60 - 11 + 1 = 50

Case 1: Perfect Square:

4^2  =16
 5^2  = 25
 6^2  = 36
 7^2  = 49

Case 2 : Perfect Cube:

3^3  = 27

We know that we need to add if it's a OR probability.

\frac{4}{50}  +  \frac{1}{50}

=  \frac{5}{50} 
=  \frac{1}{10} 
= 0.1

Thus the best answer is A.

One integer will be randomly selected from the integers 11 to 60, incl

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