5 times.
When tossing 2 pennies there are 4 equiprobable outcomes or events with 1/4 of
probability for each to happen:
P(H,H) = 1/4
P(H,T) = 1/4
P(T,H) = 1/4
P(T,T) = 1/4
So if you toss 2 pennies 20 times, the "expected" number of times that 2 heads (H,H)
will come up is 1/4 of the 20 times, that is 5 times.
A fair coin would be expected to land on heads 10 times on average.
A fair coin would be expected to land on heads 75 times.
Roughly half of the time, so about 350 times.
Expected number of heads is 1/4 * 32 or 8 heads.
This is a binomial probability distribution The probability of exactly 2 heads in 50 coin tosses of a fair coin is 1.08801856E-12. If you want to solve this for how many times 50 coin tosses it would take to equal 1 time for it to occur, take the reciprocal, which yields you would have to make 9.191019648E11 tosses of 50 times to get exactly 2 heads (this number is 919,101,964,800 or 919 billion times). If you assume 5 min for 50 tosses and 24 hr/day tossing the coin, it would take 8,743,360 years. That is the statistical analysis. As an engineer, looking at the above analysis, I would say it is almost impossible flipping the coin 50 times to get exactly 2 heads or I would not expect 2 heads on 50 coin tosses. So, to answer your question specifically, I would say none.
Each time you toss two pennies, there are four ways they can land: H H H T T H T T One of the four ways is (Heads - Heads), so the probability of 2 heads is 1/4 or 25% . If the pennies are 'fair' (not loaded), and you toss them a large number of times, you should expect 2 heads roughly 1/4 of the time. Out of 20 tosses, that's 5 times. But don't bet on it.
10
Out of the 1,000 tosses, you should expect to see 2 heads 250 times (1/4 of them), 2 tails 250 times (1/4 of them), and one of each 500 times (1/2 of them). Out of the 2,000 coin faces that show, you should expect to see very close to 1,000 heads (1/2 of them) and 1,000 tails (1/2 of them).
75
A fair coin would be expected to land on heads 10 times on average.
around 45
The probability of a heads is 1/2. The expected value of independent events is the number of runs times the probability of the desired result. So: 100*(1/2) = 50 heads
A fair coin would be expected to land on heads 75 times.
Roughly half of the time, so about 350 times.
30 maybe but i say 35 or 31
The expected number is 3750.
Expected number of heads is 1/4 * 32 or 8 heads.