Answer:
A is correct.
Step-by-step explanation:
From the second sentence , we can deduce that the total number of problems is 29.
Now, x represents the number of problems that award 5 marks, while y represents the number of problems that award 2 marks.
Hence x + y = 29.
There are a total of 100 marks. This mean each x has a mark of 5, so total x marks equal 5x. Also, each y has a mark of 2. total y marks equal 2y. Since total marks equal 100. This mean 5x + 2y = 100 which gives our second equation.
This shows A is correct.
Answer:
Step-by-step explanation:
Given that Darcie wants to donate minimum 3 blankets to donate to a homeless shelter. No of days left =60
No of days to complete one blanket = 1/(1/15) = 15 days
Hence in 60 days she has to complete ≥3 blankets
No of days she has to utilize for this will be ≥3(15)=45
No of days she can skip crocheting ≤15
Let x be the no of days crocheted and y no of days skipped
Then x+y≤60
See the graph attached as x axis for days crocheted and y for days skipped
No of blankets can be either 3 or 4.
We check first the numerical coefficients of both sides of the equation if they match if we perform the operation.
(6)(4) = 24
Then, the variables. For multiplication with the same variables, the exponents are added. In the given above,
n + 2 = 6
The value of n should be 4.
Answer:
the probability that a sample of the 35 exams will have a mean score of 518 or more is <em> 0.934 </em>or<em> 93.4%</em>.
Step-by-step explanation:
This is s z-test because we have been given a sample that is large (greater than 30) and also a standard deviation. The z-test compares sample results and normal distributions. Therefore, the z-statistic is:
(520 - 518) / (180/√35)
= 0.0657
Therefore, the probability is:
P(X ≥ 0.0657) = 1 - P(X < 0.0657)
where
- X is the value to be standardised
Thus,
P(X ≥ 0.0657) = 1 - (520 - 518) / (180/√35)
= 1 - 0.0657
= 0.934
Therefore, the probability that a sample of the 35 exams will have a mean score of 518 or more is <em>0.934 or 93.4%</em>.
Answer:
t =log(20) / 0.3 = 10*log(20) / log(1,000) - years - when the tree will have 100 branches.
Step-by-step explanation:
100 = 5 * 10^(0.3t), solve for t
Divide both sides by 5:
20 =10^(0.3t)
Take the log of both sides:
0.3t =log(20)
Divide both sides by 0.3:
Multiply the RHS by 10 / 10
t =log(20) / 0.3 = 10*log(20) / log(1,000) - years - when the tree will have 100 branches.
