Answer:
7
Step-by-step explanation:
σ = 4 ; μ =?
8.52 to the left of X
.
P(X < 8.52) = 64.8%
P(X < 8.52) = 0.648
Using the Z relation :
(x - μ) / σ
P(Z < (8.52 - μ) / 4)) = 0.648
The Z value of 0.648 of the lower tail is equal to 0.38 (Z probability calculator)
Z = 8.52 - μ / 4
0.38 = 8.52 - μ / 4
0.38 * 4 = 8.52 - μ
1.52 = 8.52 - μ
μ = 8.52 - 1.52
μ = 7
Answer:
c) 12/15 = 4/5
Step-by-step explanation:
imagine we mirror the triangle up, so that Z is on top.
then you can clearly see that 6 is cos(X) times r (and r is then 7.5).
XY is sin(X)×7.5
and again, 7.5 is r (the line making the X angle).
so, the cosine ratio of X is
6 = cos(X)×7.5
cos(X) = 6/7.5 or then 12/15. or simplified 4/5.
Box = b
Parrots = p
b/p = number of days it can support the parrots
Half a dozen = 6 (A dozen is 12)
1/6 = 15
To work out the percentage of '6' '5' is, use the equation
(5/6)*100 = 83.333....
Meaning that with one less bird, the box will support the birds for 16.666... (100 - 18.333...) longer
(15/100)*116.666... = 17.4999....
The box will sustain the parrots for 17.5 days
Answer:
C
Step-by-step explanation:
x^2 + (x+3)^2 = 117
x^2 + x^2+6x+9 =117
2x^2 + 6x - 108 = 0
(2x-12)(x+9)=0
x=-9,6
x cannot be negative therefore, x = 6
Answer:
56 cubic meter
Step-by-step explanation:
Volume of a pyramid: V=(lwh)/3
So then 7*3*8/3= 7*8 =
56 cubic meter
