Answer:
Option C.
Step-by-step explanation:
Sampling bias is a problem during the initial data gathering step of a survey.
When the first step is wrong, then the survey cannot produce non biased results.
The problem occurs when the design of the study is wrong the data collection procedure is wrong.
So, here answer seems C, because the starting point is not selected at random in this survey.
(C) Jean wants to estimate the mean amount of money spent on clothes per week by mall shoppers. She collects data from every 10th person entering a clothing store at the mall.
Answer:
Δ JKL is similar to Δ ABC ⇒ D
Step-by-step explanation:
Similar triangles have equal angles in measures
In ΔABC
∵ m∠A = 15°
∵ m∠B = 120
∵ The sum of the measures of the interior angles of a Δ is 180°
∴ m∠A + m∠B + m∠C = 180°
→ Substitute the measures of ∠A and ∠B
∵ 15 + 120 + m∠C = 180
→ Add the like terms in the left side
∴ 135 + m∠C = 180
→ Subtract 135 from both sides
∴ 135 - 135 + m∠C = 180 - 135
∴ m∠C = 45°
The similar Δ to ΔABC must have the same measures of angles
If triangles ABC and JKL are similar, then
m∠A must equal m∠J
m∠B must equal m∠K
m∠C must equal m∠L
∵ m∠J = 15°
∴ m∠A = m∠J
∵ m∠L = 45°
∴ m∠C = m∠L
∵ m∠J + m∠K + m∠L = 180°
→ Substitute the measures of ∠J and ∠L
∵ 15 + m∠K + 45 = 180
→ Add the like terms in the left side
∴ 60 + m∠K = 180
→ Subtract 60 from both sides
∴ 60 - 60 + m∠K = 180 - 60
∴ m∠K = 120°
∴ m∠B = m∠K
∴ Δ JKL is similar to Δ ABC
Hi!
So, it looks like you're doing ratios.
Let's look at 9). If the model car is 4 inches long, and 1 inch equals 4 feet, than the actual car is 16 feet long. We know this because 4x4=16.
11) is also just as simple. If 1 cm is 11 km, and the two cities are 99 km apart, then on the map they are 9 cm apart. 11x9 is 99.
13) This is a 1:2 ratio. Basically, the flagpole's shadow is half of its height. You half the man's height to get a 3 foot shadow.
And, finally, 15)- if the model is 4 inches to the real life train's 3 feet, the actual train is 120 ft long, given that the model is 40 in long. 40x3=120.
I hope this helps! :)
You have to complete the square. When you do this you get an equation that looks like this: (x-3)^2 + (y+4)^2 = 4. So your center is (3, -4) and your radius is 2. That looks like B to me!!!
