(sum is adition)
This is all truely from my head:
40 plus 20 is 60.
5 plus 6 is 11.
60 plus 11 is 71.
please mark brainliest if you think it's gucci!
Since the problem states "at least" we need to also find probability of 3 H or 4 H or 5 H
Now find the probability of flipping a head 4 times;

⁴
= (1/16)
Now probability of flipping a head 3 times: (4C3)(1/2)⁴ = 4/16
Probability of flipping a head 2 times; (4C2)(1/2)⁴=6/16
(1/16)+(4/16)+(6/16)=11/16
Probability of flipping a fair coin 4 times with at least 2 heads is 11/16.
Hope I helped :)
Answer: 7800
Step-by-step explanation:
As English alphabet has 26 letters.
So , Choices for First character in the code = 26
The choices for digits = 10 (From 0 to 9)
So , choices for second character = 10 (Middle two characters must be numbers)
choices for third character = 10 (Middle two characters must be numbers)
Choices for last character = 3 (the last character must be a 1, 3, or 7)
By Fundamental principle of counting , the total number of four character codes can be generated =
(Choices for First character)x (choices for digits) x(choices for digits) x(Choices for last character)
= (26) (10)(10)(3) =7800
Hence, the total number of character codes can be generated= 7800
I googled it and the answer is 1,800 miles