Ifa*bis defined as “half the average ofaandb”, determine the positive

difference between: (3 * 5) * 6 and 3 * (5 * 6). Express answer as a fraction in

simplest form or as an exact decimal.

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- Nov 23rd 2009, 08:56 AMsri340Arithmetic with * OperationsIf
*a***b*is defined as “half the average of*a*and*b*”, determine the positive

difference between: (3 * 5) * 6 and 3 * (5 * 6). Express answer as a fraction in

simplest form or as an exact decimal.

- Nov 23rd 2009, 09:17 AMI-ThinkIf
*a***b*is defined as “half the average of*a*and*b*”, determine the positive

difference between: (3 * 5) * 6 and 3 * (5 * 6). Express answer as a fraction in

simplest form or as an exact decimal.

If $\displaystyle a*b=\frac{1}{2}(\frac{a+b}{2})$

Then $\displaystyle a*b=\frac{a+b}{4}$

So $\displaystyle 3*5=\frac{3+5}{4}=2$

And $\displaystyle 2*6=\frac{2+6}{4}$

The rest should follow.