Jenna flips two pennies 105 times. How many times can she expect both coins to come up heads?

To solve this problem, we can use probability to determine how many times Jenna can expect both coins to come up heads after flipping them 105 times.

Step 1: Determine the probability of one coin coming up heads. The probability of a single penny landing on heads is 1/2, since there are two possible outcomes (heads or tails) and both are equally likely.

Step 2: Calculate the probability of both pennies coming up heads on a single flip. Since each coin toss is independent of the other, we can multiply the probabilities for each coin to find the combined probability: (1/2) * (1/2) = 1/4 This means that there is a 1 in 4 chance that both pennies will come up heads on any given flip.

Step 3: Determine the expected number of times both coins will come up heads after 105 flips. To find this, we simply multiply the probability found in Step 2 by the total number of flips: 105 * (1/4) = 26.25

Since you cannot have a fraction of a flip resulting in heads, Jenna can expect both coins to come up heads approximately 26 times out of 105 flips.