Let x be the number of 5 points question.
Let y be the number of 2 points question.
Total number of questions is 38
x + y = 38
Total points is 100
5x + 2y = 100
x + y = 38 ------------- (1)
5x + 2y = 100 ---------(2)
From (1):
x + y = 38
x = 38 - y -------------- sub into (2)
5(38 - y) + 2y = 100
190 - 5y + 2y = 100
3y = 90
y = 30 ------------------ sub into (1)
x + 30 = 38
x = 38 - 30
x = 8
There are 8 5-point questions and 30 2-point questions
Answer:
Below in bold
Step-by-step explanation:
The sequence is:
3, x, y, 18
If this is an A P then
x - 3 = y - x
2x - y = 3 (A) and
y - x = 18 - y
2y - x = 18 (B)
Multiply (A) by 2:
4x - 2y = 6 (C)
Adding B and C:
3x = 24
x = 8.
and
2y - 8 = 18
2y = 26
y = 13.
So x = 8 and y = 13.
b) ar + ar^2 = 6ar^3 where a = first term and r = common ratio
Divide by a:
r + r^2 = 6r^3
6r^3 - r^2 - r = 0
r(6r^2 - r - 1) = 0
r(3r + 1)(2r - 1) = 0
So the 2 possible values of r
= -1/3 and 1/2.
i) The common ratio is positive so it must be 1/2.
Second term ar = 8
1/2 a = 8
a = 16.
So the first 6 terms are:
16, 8, 4, 2, 1, 1/2.
The answer is 3.2 as a decimal. In mixed for it is 3 1/5 and in simplest form it is 16/15
Answer:
I don't know, I'm just doing this to get points. lol
Step-by-step explanation:
