Probability for either side of a fair coin: 1/2. A coin has two sides.
Probability of any side of a dice: 1/6. A cube has 6 sides.
P(number rolled on dice is less than 3: 1/6+ 1/6 = 2/6 = 1/3.
Why do we add 1/6 two times? On a cube there are 2 numbers less than 3. You know the numbers to be 1 and 2.
P(Coin is heads): 1/2
P(Coin is heads AND dice is less than 3): 1/3 x 1/2 = 1/6.
Understand?
Answer: 10a + 15b
Step-by-step explanation:
If each years cumulate an increase of 1100 dollars, then the cost after 22 years will be the base cost (27000) plus 22 increases (22*1100), for a total of
This relates to arithmetic series as follows: a series is arithmetic if, given a starting element 
, every next element is given by adding a fixed number, called common difference, 
. So, the first terms are
So, you can see that the element 
is obtained by adding n times the common ratio to the starting element.
Since the element 
represents the cost after n years, we are interested in the element
As we had already calculated.
see the attachment photo!
