Answer:

Step-by-step explanation:
Part (a) the probability that two people have a birthday on the 9th of any month.
Neglecting leap year, there are 365 days in a year.
There are 12 possible 9th in months that make a year calendar.
If two people have birthday on 9th; P(1st person) and P(2nd person).

Part (b) the probability that two people have a birthday on the same day of the same month
P(2 people selected have birthday on the same day of same month) + P(2 people selected not having birthday on same day of same month) = 1
P(2 people selected not having birthday on same day of same month):

P(2 people selected have birthday on the same day of same month) 
Answer:
Step-by-step explanation 10 + 2.50d = 850
David starts with $10 and each day he earns $2.50. The d represents a variable and can be any number.
To find d you must solve the equation.
10 + 2.50d = 850
2.50d = 840 (subtract 10 from 850)
d = 336 (divide 840 by 2.50)
It will take David 336 days to save $850.
I think it’s 30 not gonna lie I’m gonna get somebody
Let’s see if there’s anyone!!!!!!!!!!!!
A.
Answer:
all work is shown and pictured
For this ones the second value is always negative so A is not correct. Also they have to have an exact square root which 50 doesn't. So the answers are B and C
(a-6)(a+6)
(w-11)(w+11)