Ten coins are tossed simultaneously. In how many of the

Question

Ten coins are tossed simultaneously. In how many of the outcomes will the  third coin  turn up a head?

A. 210
B. 29
C. 3*28
D. 3*29
E. None of these

jdtomatito · Answer

I thinnk it is E, 2^9 would be the answer as we have nine coins with two possible outcomes each

MBAHopeful · Answer

I came up with E too!

ranga41 · Answer

I get  2^8 ,

 2^9 possible outcomes for other coins and half of that for the third coin being head and half for it being tail...

duttsit · Answer

Could you explain pls.
I thought 2^9 outsomes from other coins will be for their coin being head AND another 2^9 outcomes from other coins for it to be tail (total outcomes 2^10)

gandy_achar · Answer

I got 2^9 outcomes with heads in the third round. Whats the OA?


GA

tikpaklong · Answer

Ten coins are tossed simultaneously. In how many of the outcomes will the third coin turn up a head?

A. 2^10
B. 2^9
C. 3*2^8
D. 3*2^9
E. None of these

GMAT TIGER · Answer

i think the answers should be the followings:

A. 2^10
B. 2^9
C. 3*2^8
D. 3*2^9
E. None of these

I take 2^9.

singh_amit19 · Answer

My answer: 2^9.............i suppose it's B

tikpaklong · Answer

sorry about the answer choices...yes the official answer is 2^9. Can you guys explain? I'd appreciate it. Thanks.

sonibubu · Answer

Total possible outcomes is 2^10

In half the outcomes, the third coin will be tails (in the other half it will be heads).

(2^10)/2 = 2^9

This is also the number of outcomes where the third coin will come up heads.

kidderek · Answer

Basically, the question asks how many different outcomes are there if you toss up 10 coins. The answer to that is 2^10

But since the third coin is heads, we divide the total number of combinations by 2, thus (2^10)/2 = 2^9

OR

How many different outcomes can there be for the 9 remaining coins if the third one is heads? 2^9

garyxb · Answer

Great explanation, I am not new to the forum, but I have not been paticipating in the math section...so I am not familiar with the symbals...

Question: 2^9, does this mean 2 to the 9th power??? I am assuming it is...

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Ten coins are tossed simultaneously. In how many of the

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