Answer: The test contains 10 three-point questions and 14 five-point questions.
Step-by-step explanation:
Let x represent the number of 3-point questions.
Let y represent the number of 5-point questions.
The maths test consists of 24 questions. This means that
x + y = 24
Each question is worth either 3 points or 5 and the test is worth 100 points. This means that
3x + 5y = 100 - - - - - - - - - - -1
Substituting x = 24 - y into equation 1, it becomes
3(24 - y) + 5y = 100
72 - 3y + 5y = 100
- 3y + 5y = 100 - 72
2y = 28
y = 28/2 = 14
Substituting y = 14 into x = 24 - y , it becomes
x = 24 - 14 = 10
Answer:
E is not a subspace of 
Step-by-step explanation:
E is not a subspace of
In order to see this, we must find two points (a,b), (c,d) in E such that (a,b) + (c,d) is not in E.
Consider
(a,b) = (1,1)
(c,d) = (-1,-1)
It is easy to see that both (a,b) and (c,d) are in E since 1*1>0 and (1-)*(-1)>0.
But (a,b) + (c,d) = (1-1, 1-1) = (0,0)
and (0,0) is not in E.
By the way, it can be proved that in any vector space all sub spaces must have the vector zero.
Question 1132387: How many liters of a 10% solution should be mixed with 60L of 25% solution to get 15% solution? = one click in Excel = 120. ANSWER. 120 liters of the 10% solution.