Answer:
6
Step-by-step explanation:
Since RQ bisects WRV, WRQ = QRV, 48=7y+6. 48-6=42, leaving 42=7y. 42/7=6.
Answer:
Price went up, $24.64/year for 28 years
Step-by-step explanation:
Change Year = 28
Change Price = 690
Average rate = 690/28 = 24.64
Answer:
The traveler can plan such a tour in 3003 ways.
Step-by-step explanation:
The order that the cities are chosen is not important, since it is chosen by the company and not by the traveler. So we use the combinations formula to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.

In this problem, we have that:
Combinations of 5 cities from a set of 15. So

The traveler can plan such a tour in 3003 ways.
2000(3/5)
6000/5
1200
So 1200 doctors used brand X
This is a sum and difference problem, with the equations
R-N=35
R+N=635
The solution of which is
R=(635+35)/2=335
N=(635-35)/2=300
In general, the sum and difference problem can be solved (most of the time mentally) using
Larger number = (sum + difference)/2
Smaller number = (sum - difference)/2