Aininor
1
<p>This is from the Blue Book Practise test 5 Section 7 Q15</p>
<p>How many integers in the set of all integers from 1 to 100, inclusive, are not the square of an integer?</p>
<p>A) 19
B) 50
C) 81
D) 89
E) 90</p>
<p>This was my method and I got it wrong - so some feedback would be much appreciated!</p>
<p>There are 101 integers from 1 - 100 inclusive
there are 10 integers that are the square of an integer (1, 4, 9, 16...81, 100)
so 101-10 = 91</p>
<p>but the answer is E) 90</p>
<p>Please help, thanks ;)</p>
Miriel
2
<p>I think that there are 100 integers from 1-100 inclusive. There would be 101 integers if the problem asked for 0-100.</p>
<p>Sometimes it gets really confusing at times, but the rule I just remember is:</p>
<p>1 to C ( C being any integer) = C integers in that set</p>
<p>0 to C = C + 1 integers in that set.</p>
<p>There are 100 integers and not 101 integers from 1-100 inclusive.
For instance in a set of integers 1-2 inclusive there are 2 integers-1 & 2</p>
<p>The rule to follow is between A to B exclusive there are B-A-1 integers.
And in between B to A inclusive there are B-A+1 integers.</p>
<p>Oh gosh, what a stupid mistake to make :( Ugh and I was sitting there for like 5 min stumped when it was so glaringly obvious!</p>
<p>Thanks for the trick everyone! :)</p>