Answer: a. 0.14085
b. 3.826 x 
c. 0.5437
d. 0.0811
Step-by-step explanation:
Given average amount parents and children spent per child on back-to-school clothes in Autumn 2010 , 
= $527
Given standard deviation , 
= $160
Let X = amount spent on a randomly selected child
Also Z = 
a. Probability(X>$700) = P( > 
) = P(Z>1.08125) = 0.14085 {Using Z % table}
b. P(X<100) = P( Z < 
) = P(Z< -2.66875) = P(Z > 2.66875) = 3.826 x
c. P(450<X<700) = P(X<700) - P(X<=450)
P(X<700) = 1 - P(X>=700) = 1 - 0.14085 = 0.8592
P(X<=450) = P(Z<= 
) = P(Z<= -0.48125) = P(Z<=0.48125) = 0.3155
So final P(450<X<700) = 0.8592 - 0.3155 = 0.5437
d. P(X<=300) = P(Z<= 
) = P(Z<= -1.4188) = P(Z>=1.4188) = 0.0811
All the above probabilities are calculated using Z % table along with interpolation between two values.
Answer:
3:2
Step-by-step explanation:
2 boys for every 3 girls
Answer:
16.1 km
Step-by-step explanation: 10mi x 1.61=16.1km
Answer:
you first start by making your equation: 45 +.25x = 70 +.15x. then subtract .15x from both sides. it should look like 45 +.10x = 70. subtract 45 from both sides then you get .10x = 25. divide 10 to both sides and you get 250. so the two companies will be the same at 250 texts.
Step-by-step explanation:
Answer:
y = 52500(.91)^x
Step-by-step explanation:
Exponential functions are written y = ab^x where a is the starting point and b is the common ratio. We know the initial worth is 52500 and each year the worth decreases 9% of the original year, making it work 91% of the previous value.
