PSAT help!

G

Guest

Guest
Let the operation @ be defined for all integers r and s by r@s=s what is the value of 2@(3@4)

The answer is 4. but I don't know how to do the problem
 
Well, if r@s=s, that means if two numbers are @-ed, only the second one remains...

so

24@7=7
1@0=0
53@28=28

and so on...

back to the problem 2@(3@4)

We do the things in the parentheses first, so
2@(3@4)

Since 4 is second, it "gets rid of" 3.

2@(4), or 2@4,

which evaluates to just

4
 
If this be the full problem, then the operation leaves you the second number out of the two.
By order of operations:

3 @ 4 = 4 => we get 2 @ 4
2 @ 4 = 4 => that's the final answer
 
You must log in or register to reply here.
Top