<p>*. Chairs ready for shipment at the Northern Chair
factory come down a ramp in single file. Inspector A
checks every third chair, beginning with the third.
Inspector B checks every fifth chair, beginning with
the fifth. If 98 chairs came down the ramp while both
inspectors were working on Monday, how many of
these chairs were not checked by either of these two</p>
<h2>inspectors?</h2>
<p>i would really appreciate your feedback '
thanx</p>
<p>any one ?
i have more :(
**How many positive integers less than 1001 are divisible by either 2 or 5 or both?</p>
<p>a.300
b.400
c.540
d.600
e.700</p>
<p>n = 1234567891011 . . . 787980</p>
<p>The integer n is formed by writing the positive integers
in a row, starting with 1 and ending with 80, as shown
above. Counting from the left, what is the 90th digit
of n ?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5</p>
<p>Your first question is essentially looking at how many numbers between 1-98 are not divisible by 3 or 5. That first inspector will inspect 32 chairs (his last chair will be the 96th). The second inspector will inspect 19 chairs (the last being the 95th). Now what do you do, you subtract the number of chairs they have in common. Every 5 chairs Inspector A inspects, B does as well. So to eliminate double counting of the inspected chairs we subtract the number they inspect in common. In this case, that would be 6 (32/5, and we don't care about remainder).</p>
<p>So: 19 + 32 - 6 = 45 uninspected chairs.</p>
<p>Positive Integers:</p>
<p>This has the same thought process as before: the "Or both" clause is completely unnecessary. There are 500 positive numbers less than 100 that are divisible by 2 (of course, the even numbers). Now there are 200 numbers divisible by 5. For every 5 numbers divisible by 2 you reach a number divisible by 5 (check this out yourself). So again 500/5 = 100 numbers divisible by 5 and 2 - this makes sense since that means the number that are divislbe by 10 which is 2 times 5 anyway. So: 500 + 200 - 100 = d. 600</p>
<p>The last one requires a bit more thinking. The first nine digits are 1-9, and the next 20 make up 10-19. So 9 digits (1-9) + 20 digits (10-19) + 20 digits (20-29) + 20 digits (30-39) + 20 digits (40-49) = 89th digit. That means the 90th digit is the beginning of the next group or e. 5</p>
<p>Fajas - cc'ers might be weary of taking a risk of getting from you<br>
'you answered my @#$%^ question wrong!!'
in place of ty and refrain from helping your maths! :D</p>