Mathspapa a website that will help.
Answer:
532
Step-by-step explanation:
The score that represents the top 20% = A score = 80%
Z score for 80% percentile = 0.842
We solve using the z score formula
z = (x-μ)/σ, where
x is the raw score = ??
μ is the population mean = 490
and σ is the population standard deviation = 50
Hence:
0.842 = x - 490/50
Cross Multiply
0.842 × 50 = x - 490
x = 0.842 × 50 + 490
x = 42.1 + 490
x = 532.1
Approximately = 532
Therefore, the test score = 532
Answer:
Step-by-step explanation:
Area of outer triangle = 
= 2x*4x + 2x*3
= 8x² + 6x
Area of inner triangle= 
Area of aluminium = area of outer triangle - area of inner triangle
= 8x² + 6x + 2x² + 5x
= 10x² + 11x
Area of 20 aluminum borders = 20*(10x² + 11x) = 200x² + 220x
b) x = 25 cm
Area of 20 aluminum borders = 200*25² + 220*25
= 200 * 625 + 220*25
= 125000 + 5500
= 130500 cm²
c) Area of inner triangle (Glass) = 5500 cm²
Cost of aluminium = 130500 * 0.06 = $ 7830
Cost of glass = 5500 * 0.03 = $ 165
Cost of making 20 windows = 7830 + 165 = $ 7995
d-13=5 is actually suppose to be solved liek this:
d - 13 = 5
+13 +13
The absoulte value of 13 is 13, it is negative so you have to add 13 to get to 0 so it can be cancelled out.
Answer:

Step-by-step explanation:
Mei's horse is 3 meters from the center of the carousel. After one rotation, Mei travelled

Anju's horse is 2 meters from the center. After one rotation, Mei travelled

The difference in their travelled distances is
