Answer:
Step-by-step explanation:
b and c are the speeds of the boat in stool water, and current, respectively.
Going with the current, the boat travels b+c=16 km/h.
Going against the current, the boat travels b-c=6 km/h
add the equations together
b+c = 16
b-c = 6
—————
2b = 22
b = 11
c = 16-b = 5
Answer:
They have the same mustard flavor!
Answer:
A) Length = 110.4 mm and width = 62.1 mm
B) A = 6855.84 mm²
C) length = 114.7 mm
width = 55.8 mm
Area = 6400.26 mm²
D) Screen with aspect ratio of 16:9 is bigger
Step-by-step explanation:
A) We are told that the aspect ratio of the phone screen = 16:9. This means that the ratio of the length to the width of the screen is 16:9.
To find the side length, we will say that;
length = 16x
width = 9x
Thus, since the edges are perpendicular, then we can use pythagoras theorem since we know that the diagonal is 127 mm
Thus;
(16x)² + (9x²)] = 127²
256x² + 81x² = 16129
337x² = 16129
x² = 16129/337
x = √(16129/337)
x = 6.9
Thus;
length = 16x = 16 × 6.9 = 110.4 mm
width = 9x = 9 × 6.9 = 62.1 mm
Length = 110.4 mm and width = 62.1 mm
B) area of screen is;
A = length × width
A = 110.4 × 62.1
A = 6855.84 mm²
C) We are told that the aspect ratio is now 18.5:9.
Thus;
length = 18.5x
width = 9x
Thus;
(18.5x)² + (9x²)] = 127²
342.25x² + 81x² = 16129
423.25x² = 16129
x² = 16129/423.25
x = √(16129/423.25)
x = 6.2
length = 18.5x = 18.5 × 6.2 = 114.7 mm
width = 9x = 9 × 6.2 = 55.8 mm
Area = 114.7 × 55.8 = 6400.26 mm²
D) Screen with aspect ratio of 16:9 is bigger
€1 = $1.10
€90 = $99
$99 - $63 = $36
$36 / $1.20 = $30
$36 = €30
Answer €30
You're going to have to work out the z-scores of both values in each option and see if it makes sense.
n = m + sz
The mean is 20 and the standard deviation is 3.
So let's find try the z-scores of the outer range values and determine their probabilities:
from 14-20:
n = m + sz
20 = 20 + 3z and 14 = 20 + 3z
0 = 3z and -6 = 3z
z = 0 and z = -2
So now using a z-score table, such as the one below, find the probabilities.
z = 0 is easy, it's 0.5
z = -2 is 0.02275
Subtract the smaller from the larger to get the probability of getting in the range:
0.5 - 0.02275 = 0.47725 (so times 1000, you get 477.25, which is not about 340, so this option is wrong)
---
Now trying option 2, from 17-29:
n = m + sz
29 = 20 + 3z and 17 = 20 + 3z
9 = 3z and -3 = 3z
z = 3 and z = -1
0.99865 - 0.158655 = 0.839995 (not 680, so not the answer)
---
Now trying option 3, from 20-23:
n = m + sz
23 = 20 + 3z and 20 = 20 + 3z
3 = 3z and 0 = 3z
z = 1 and z = 0
0.841345 - 0.5 = 0.341345 (close to 340, so is your answer)
