# MemberShip Tables

Show 40 post(s) from this thread on one page
Page 2 of 2 First 12
• Jul 17th 2010, 07:09 AM
ramdrop
How did you do that, I really don't see where the -10, 13 and 15 came from unless im being really stupid :|
• Jul 17th 2010, 09:45 AM
undefined
Quote:

Originally Posted by ramdrop
How did you do that, I really don't see where the -10, 13 and 15 came from unless im being really stupid :|

That was a hypothetical example; I meant for you to use it as a model to solve the actual problem. It was so that I could show you how to do it without actually solving the problem for you.
• Jul 17th 2010, 11:14 PM
ramdrop
Oh right okay, well I solved it to have:

\$\displaystyle -4 \le x \le 7\$

Seeing as -4 is impossible the smallest value must be 0 and the maxium, 7
• Jul 17th 2010, 11:32 PM
undefined
Quote:

Originally Posted by ramdrop
Oh right okay, well I solved it to have:

\$\displaystyle -4 \le x \le 7\$

Seeing as -4 is impossible the smallest value must be 0 and the maxium, 7

You seem to have kept the loosest bounds and discarded the strictest.

\$\displaystyle \displaystyle x \ge 0\$

\$\displaystyle 7-x \ge 0 \implies x \le 7\$

\$\displaystyle 6-x \ge 0 \implies x \le 6\$

\$\displaystyle 4+x \ge 0 \implies x \ge -4\$

Discarding the second and fourth, I get \$\displaystyle 0 \le x \le 6\$ .

IMPORTANT: x is not the value you seek to find the min and max of. You want to find min and max of "the number of male patients under 50 without a back problem" which is 7-x. So...
Show 40 post(s) from this thread on one page
Page 2 of 2 First 12