Answer:
225
Step-by-step explanation:
Using the basic components of summation ∑
∑n = 
n(n + 1) and ∑1 = n
Thus
∑ (2n - 1) ← for n = 1 to 15
= ∑2n - ∑1
= 2∑n - ∑1
= 2 ( n(n + 1)) - n
= n(n + 1) - n ← Evaluate for n = 15 ( the upper value )
= 15 × 16 - 15
= 240 - 15
= 225
Answer: I really don't know yet.
Step-by-step explanation:
Another day. 
Answer:
3(9m + 13) - (m + 10) = 1
Step-by-step explanation:
Here, we want to write an equation we can use to find the age of Mario.
Let the present age of Mario be M
Age of Sarah is 3 years older than 9
times Mario’s age
Mario’s age is thus;
9m + 3
In ten years, she will be 1 less than triple his age
In 10 years time, sarah age will be 9m +
3 + 10 = 9m + 13
Mario age will be m + 10
Mathematically;
3(9m + 13) - (m + 10) = 1
Answer:
D 46x²+ 67x -16
Step-by-step explanation:
adding like terms
R1(x) + R2(x) = 16x²+52x-27 + 30x² + 15x + 11
total = 46x²+ 67x -16
Remark
You cannot give an answer to this unless you are give the fastest speed of a swimmer. That stat is not an easy one to decide upon. At what distance for example or do you eliminate distance? Since this is a college level question, I don't think it unreasonable that you have to research raw distance over fastest time.
The fastest speed I can find is 100 meters in 46.91 seconds. That means that the actual speed of the swimmer is 100 meters / 46.91 = 2.132 meters / second.
Givens
Set up a proportion with the numbers found and given
Speed of ball / speed of swimmer = 21.12 / 1
Speed of ball = x
Solution
Speed of swimmer = 2.132 m/s
x / 2.132 = 21.12 / 1 Multiply Both sides by 2.132
x = 21.12 * 2.132 / 1
x = 45.02 m/s
Answer
45.02 m/s
