9514 1404 393
Answer:
(c) 2440
Step-by-step explanation:
The sum of the squares of numbers 1 .. n is ...
s(n) = n(n +1)(2n +1)/6
You want the sum of squares from 5 to 19. We can compute that from ...
s(19) -s(4) = (19(20)(39) -4(5)(9))/6 = (14820 -180)/6 = 2440
Area = length x width.
24 = (x + 2)(x - 3) = x² - x - 6
x² - x - 30 = 0
(x + 5)(x - 6) = 0
We can eliminate the root x = - 5 because dimensions cannot be negative. So, the only valid answer is x = 6
The length = x + 2 = 6 + 2 = 8 in.
The width = x - 3 = 6 - 3 = 3 in.
72 is the minimum grade he must get on the last test in order to have an average of 77.
<u>Step-by-step explanation:</u>
The grades of a student are given 72,91,78,72 and the grade of his last test is not given.
- You have to find the minimum grade the student shall get, so that the student average must be 77.
- The four grades are already given. Therefore, we need to find only the fifth grade.
The term average is defined as the sum of all the data in a set divided by the number of data in a set.
Here, the number of data is 5. (Because the students has 4 grades plus one grade for his last test).
The average he should get is 77.
Average = Sum of all grades / number of grades
Let, 'x' be the grade of the last test.
⇒ 77 = (72+91+78+72+x) / 5
⇒ 77 = (313+x) / 5
⇒ 385 = 313 + x
⇒ x = 385 - 313
⇒ x = 72
The minimum grade he must get on the last test is 72.
THat would be A , B, C and E
Answer:
17.9
Step-by-step explanation:
3.7²+17.5²=319.94
= 17.9