Answer:
Base=8 feet
Height=17 feet
Step-by-step explanation:
Let
Base=x
Height=3x-7
Area=68 square feet
Area of the sail boat=1/2 * base * height
68 = 1/2 * x * (3x-7)
Cross product
68 * 2 =(1) * (x) * (3x-7)
136 = 3x^2 - 7x
3x^2 - 7x - 136=0
Using quadratic formula
x= -b +or- √b^2 - 4ac / 2a
= -(-7) +or- √(-7)^2 - (4)(3)(-136) / 2(3)
= 7 +or- √49 - (-1632) / 6
= 7 +or- √49+1632) / 6
= 7 +or- √1681 / 6
=7 +or- 41 /6
x= 7+41 / 6 or 7-41 / 6
=48/6 or -34/6
=8 or -17/3
Answer:
Step-by-step explanation:
Let
Base=x
Height=3x-7
Area=68 square feet
Area of the sail boat=1/2 * base * height
68 = 1/2 * x * (3x-7)
Cross product
68 * 2 =(1) * (x) * (3x-7)
136 = 3x^2 - 7x
3x^2 - 7x - 136=0
Base of the boat can't be a negative value
Therefore,
Base = x = 8 feet
Height= 3x-7
=3(8)-7
=24-7
=17 feet
Answer: D) 10 jerseys
Step-by-step explanation:
Let j represent the number of jerseys and C for total cost
Local company eqn: C = 5.25j + 45
Online company eqn: C = 7.75j + 20
Set both sides equal to solve:
5.25j + 45 = 7.75j + 20
5.25j - 7.75j = 20 -45
- 2.5j = -25
j = 10
Therefore, the cost is the same for both companies when 10 jerseys are sold
Answer:
b
Step-by-step explanation:
b
This question is incomplete, the complete question is;
X and Y are independent Gaussian (Normal) random Variables. X has mean 13.9 and variance 5.2; Y has mean 6.9 and variance 3.8. . (a) Calculate P( W> 10)
Answer:
P( W> 10) is 0.1587
Step-by-step explanation:
Given that;
X ⇒ N( 13.9, 5.2 )
Y ⇒ N( 6.9, 3.8 )
W = X - Y
Therefore
E(W) = E(X) - E(Y)
= 13.9 - 6.9 = 7
Var(W) = Var(X) + Var(Y) -2COV(X.Y)
[ COV(X,Y) = 0 because they are independent]
Var(W) = 5.2 + 3.8 + 0
= 9
Therefore
W ⇒ N( 7, 9 )
so
P( W > 10 )
= 1 - P( W ≤ 10 )
= 1 - P( W-7 /3 ≤ 10-7 /3 )
= 1 - P( Z ≤ 1 ) [ Z = W-7 / 3 ⇒ N(0, 1) ]
from Standard normal distribution table, P( Z ≤ 1 ) = 0.8413
so
1 - P( Z ≤ 1 ) = 1 - 0.8413 = 0.1587
Therefore P( W> 10) is 0.1587
