Symbol * denote to be one of the operations add, subtract, multiply, o

Question

Symbol * denotes one of the operations: add, subtract, multiply, or divide. 
Is  (6*2)*4=6*(2*4) ?

1)  3*2>3  
2)  3*1=3

Staphyk · Answer

This question is basically asking wether * is associative and we know only addition/mulplication is true 
(6+2)+4= 6+(2+4)
(6•2)•4= 6•(2•4)
(Stat.1) 3*2 >3 true only when * is adding or multiplying —> 3+2 > 3 or 3•2 > 3. (suff.)
(Stat.2) 3*1=3 true only when * is multiplying or dividing (not associative) (not suff)
Answer is A

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Ishat16189 · Answer

(6∗2)∗4=6∗(2∗4) holds true only if * denotes add or multiply

1) 3∗2>3
* can be Add or multiply
* can NOT be subtract or divide
we have only one answers for question "Is (6∗2)∗4=6∗(2∗4)(6∗2)∗4=6∗(2∗4)? " 
Yes if * denotes multiply
Yes if * denotes add
 SUFFICIENT

2) 3∗1=3
* can be multiply or divide
we have two different answers for question "Is (6∗2)∗4=6∗(2∗4)(6∗2)∗4=6∗(2∗4)? " 
Yes if * denotes multiply
No if * denotes divide
 NOT SUFFICIENT

Kshitij609 · Answer

But doesn't the question asks the symbol to be one of the operations? Going by that answer should be c

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aritranandy8 · Answer

VeritasKarishma  plz solve this question

KarishmaB · Answer

Is  (6*2)*4=6*(2*4) ?

If the symbol is 'add' or 'multiply', the brackets become irrelevant. The two sides will be equal. 
But if it is subtract or divide, the brackets play a role in deciding what the final answer will be.

So the question boils down to "Does the symbol denote add/multiply?"

1)  3*2>3

If the symbol were subtract or divide, 
3 - 2 < 3
and 3/2 < 3

So the symbol MUST be add or multiply. Then the answer is yes. Sufficient.

2)  3*1=3

Here, the symbol could be multiply or divide because in both cases it holds.
3 * 1 = 3
3/1 = 3

Then can we say whether the symbol is add/multiply? No. It may be multiply or it may be divide. Not sufficient.

Answer (A)

ManyataM · Answer

Can you help me understand in this way it will have two options for the symbol? but dnt we need one as the ques says symbol * denote to be one of the operations, add, subtract, multiply or divide?

Pritishd · Answer

Kshitij609  &  ManyataM

It means that  *  stands for only 1 operation during a single instance, but can be another operation at another instance E.g. S1 tells us that  *  could be addition or multiplication. Now  (6 * 2) * 4 = 6 * (2 * 4)  can be solved once by replacing  *  with  +  i.e.  (6 + 2) + 4 = 6 + (2 + 4)  and another time by replacing  *  with  *  i.e.  (6 * 2) * 4 = 6 * (2 * 4) , but you cannot combine them at the same time i.e.  (6 + 2) * 4 = 6 * (2 + 4)

So by stating  Symbol  *  denotes one of the operations  its preventing you from combining multiple operations in a single instance, but you are free to apply different operations at different instances

Hope its clear!

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Symbol * denote to be one of the operations add, subtract, multiply, o

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