Answer:
The upper bound is 399.5
Step-by-step explanation:
Let's start by calculating the mean value of the distribution as the addition of all values given divided by 12:
Average = 289.75.
If the standard deviation is 56, then the upper bound in 95% the confidence interval for the mean price of the phones is going to be given by the mean value added to 56 times 1.96 (since 95% of the population is withing 1.96 times the standard deviation)
That is: 289.75 + 56 * 1.96 = 399.51
which rounded to one decimal place gives: 399.5
A vector is basically an arrow that tells you where to go. Specifically it tells you a direction and how far. The direction component is the angle. The "how far" component is the magnitude or modulus or length of the vector.
For choice C in the upper right hand corner, we see that the vector 'a' starts off on the right side and points directly to the left. It's a horizontal vector. The arrow is at the left side. After going from tail to tip along vector 'a', we repeat the same motions for vector b. Think of it as following directions on a map. To take a shortcut, we follow the resultant vector r. This takes us from the tail of vector 'a' to the tip of vector b without any obstacles or deviations. So this is why choice C is the answer.
Note: if you use the parallelogram law for choice A, then the resultant vector will be the same as shown in choice C. This is of course assuming that each vector 'a' is the same length and direction between the two answer choices. The same assumption is for the b vector as well. Choice D is close to what choice C is saying, but the arrow for r is pointed the wrong way. The arrow head must be pointed at the tip of vector b which is the final destination we want.
30 inches is longer than 2 feet
Part a:
this is really just intuition. you can go either way as long as you back up what you say.
either you think hunter would be faster because he starts out with a lot more money, or you think amado would be faster because he earns a lot more.
part b:
let x be the number of hours hunter works, and y the number that amado works.
they both need to earn 600 dollars.
hunter's money is modelled by 150 + 7.5x
to get 600 dollars
150 + 7.5x = 600
7.5x = 450
x = 60
amado's money is modelled by 12y
to get 600 dollars
12y = 600
y = 50
hunter would need to work 60 hours to make enough money, but amado would only need to work 50, so hunter will take longer.
then say whether this agrees with what you guessed in part a
Can you explained the triangle. bad pic