In flipping a coin, heads and tails are mutually exclusive events (a coin can't show both heads and tails at the same time). If two coins are flipped, the outcomes may be heads-heads, heads-tails, tails-heads, or tails-tails. However, tails plus heads can occur in two ways. Therefore the probability of getting a tails-plus-heads combination is.....?

Question

jim_thompson5910 · Answer

Hint: The sample space looks like this

HH
HT
TH
TT

where H stands for heads and T stands for tails

driftracer305 · Answer

right

jim_thompson5910 · Answer

So count the number of ways to get tails and heads together. Then divide that by 4 (since there are 4 total possible combos)

driftracer305 · Answer

im just confused.....does this take to the product or sum rule or something totally different?

driftracer305 · Answer

ok so that is 1/2...

jim_thompson5910 · Answer

yes 2/4 = 1/2

jim_thompson5910 · Answer

I'm not sure about the product or sum rule part you asked about. It doesn't seem like you need either rule.

driftracer305 · Answer

gotcha

driftracer305 · Answer

so would that mean   1/4 + 1/4 = 1/2 ?

jim_thompson5910 · Answer

yeah I guess you can think of it like that

1/4 + 1/4 = (1+1)/4 = 2/4 = 1/2

driftracer305 · Answer

right becoz one event HT occurs 1/4  and the other... TH also 1/4.....but i dont completely understand why it is a sum rule here then....

driftracer305 · Answer

Thanks @jim_thompson5910 !

shkh.zain · Answer

Addition rule is applied when there is a word "or" used. 
E.g.
Getting a head or tail