Berkeley CSUA MOTD:Entry 52671
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2018/01/20 [General] UID:1000 Activity:popular
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2009/3/3-5 [Computer/SW/Security, Computer/SW/Unix] UID:52671 Activity:high
3/3/9   Happy Square Root Day
        \_ This morning some guy on KCBS AM 740 was playing with this and said
           something like "if you take the square root of every number, they
           don't look so big anymore.  For example, next week the square root
           of my age is just 8.  And the square root of the $838 billion
           stimulus package is just $29 billion."
           No wonder American kids rank last in math among industrialized
           countries.
           \_ i think the sqrt of his iq is also 8.
           \_ Dude needs to go back to school, and age 8 seems like a good
              time to learn about square roots.
              \_ Huh? I don't see anything wrong with his statement.
                 \_ sqrt(838e9) is about 915423.
                    \_ I guess. sqrt(838) =~ 29. (Billion dollars) is the
                       units. Depends on how you look at it.
                       \_ Right, but you need to square root the units too,
                          just like sqrt(10000 m^2) = 100 m.  The answer is
                          the same whether you consider the units to be m^2
                          or (10000 m^2) or whatever.
                          \_ I understand this, but what is the square
                             root of "2 dollars"? This is like asking what
                             is the square root of "2 cows". The original
                             statement said "square root of every number"
                             and not "square root of every quantity". You
                             could argue (correctly) that 838,000,000,000
                             is a number in itself and its root is not
                             29,000,000,000, but what about "838 cows"? What
                             is the square root of a cow? I think the key
                             number is 838 and not 838*(units). You have
                             to be pretty pedantical to not realize that.
                             \_ If your units are billions of dollars than
                                your square root units of ~ 31622 * $^(1/2).
                                  sqrt (838) * sqrt (1,000,000,000) ~=
                                  29 * 31622 ~=
                                  915422
                                  \_ 915422 *what*? Not dollars.
                                   \_ $^(1/2)  Which is 1/31622 of
                                      (Billion $)^(1/2)
                                      \_ Exactly, which is nonsense. So
                                         ignore the units.
                                         \_ If you ignore the units you can
                                            turn it anything you want.
                                            Sqrt($838e9) = $838e9 if my
                                            units are "$838e9" and I've
                                            decided units are meaningless.
                                            \_ You have to use some common
                                               sense here. The square root
                                               of his age (64) is 8, not
                                               8 (years)^1/2.
                                               \_ But by your logic we can
                                                  make the units billions of
                                                  years, and now the the
                                                  square root of 64 is
                                                  252982.
                                Better example: the square root of $1 is 1 if
                                you are ignoring units, but the square root
                                of 100 pennies is 10!  100 pennies = 1 dollar
                                so how can those two be different.
                                $1 = 100c
                                sqrt($1) = sqrt(100c)
                                1 * $^(1/2) = 10 * c^(1/2)
                                The difference is in the units.  1 c^(1/2)
                                is, by definition, 1/10th of 1 $^(1/2).
                                \_ But what is a sqrt($)? or a sqrt(cent)?
                             \_ I guess you're right.  Square rooting a number
                                independently of its unit like this makes no
                                sense, but it is what the original statement
                                said, and really it doesn't sound like he was
                                trying to make sense anyway.  (FWIW, I think
                                sqrt("2 cows") is meaningless too, unless you
                                can come up with a meaning for 1.4 cow^(1/2).)
                       \_ Depends on how good you are at math, actually.
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