Arithmetic

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Re: Arithmetic

by logitech » Sat Dec 13, 2008 5:07 pm
vladmire wrote:Why do I care if none of the numbers are greater than 60 couldn't I just say

x+x+9+10/4=30?
Okay let's say you can say that:

2x= 120-19

2x = 101 ( By the way you just assumed that remaning two numbers are equal )

x = 50.5 and B is the answer in your case

BUT

the question says FOUR DIFFERENT numbers

so X+Y =101

we are trying to find the numbers > 30

Lets say they are both bigger than 30

50 + 51 BINGO

or one of them is less than 30

29 + 72 BINGO

so we have two different answers ( they both cannot be less than 30 )

SO INSUF

But statement A gives us a clue: None of the numbers are > 60

so 29, 72 wont work.

lets try 60

60+41 , so 2 numbers are greater than 30

Can we get only one number greater than 30 ? No we can not!

So answer is 2 numbers!

And we need both statements, so C will be the correct answer
LGTCH
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by cramya » Sat Dec 13, 2008 7:03 pm
Stm I

None of the 4 different numbers greater than 60

set = {10,20,30,60}

Answer is: 1

set = {10 20 40 50}

answer : 2

INSUFF

Stmt II

Two of the 4 numbers are 9 10

set = { 9,10,11,90}

answer : 3

set = {9,10,40,61}

answer : 2

INSUFF

Combine

9+10+a+b / 4 = 30

a+b = 101

If u try to make up value for a to be <=30 then b would be greater than 60 so each number has to greater than 30

One definite answer for how many numbers greater than 30

SUFF

Choose C)