Answer:
B) 18 ft
Step-by-step explanation:
The scale is 1 in. model : 6 ft real.
6/1 = 6
To go from model size to real size, multiply the model size by 6 and change from inches to feet.
3 in. model = 3 × 6 ft = 18 ft
Answer:
a. 0.689
b. 0.8
c. 0.427
Step-by-step explanation:
The given scenario indicates hyper-geometric experiment because because successive trials are dependent and probability of success changes on each trial.
The probability mass function for hyper-geometric distribution is
P(X=x)=kCx(N-k)C(n-x)/NCn
where N=4+3+3=10
n=2
k=4
a.
P(X>0)=1-P(X=0)
The probability mass function for hyper-geometric distribution is
P(X=x)=kCx(N-k)C(n-x)/NCn
P(X=0)=4C0(6C2)/10C2=15/45=0.311
P(X>0)=1-P(X=0)=1-0.311=0.689
P(X>0)=0.689
b.
The mean of hyper-geometric distribution is
μx=nk/N
μx=2*4/10=8/10=0.8
c.
The variance of hyper-geometric distribution is
σx²=nk(N-k).(N-n)/N²(N-1)
σx²=2*4(10-4).(10-2)/10²*9
σx²=8*6*8/900=384/900=0.427
<span>You can remember by the acronym: PEMDAS which stands for p<span>arenthesis, exponents, multiply, divide, add, subtract
So you start with anything in parenthesis
</span></span>
Let the number be a
6a - 20 = 3a + 4
Group like terms
6a - 3a = 20 + 4
3a = 24
divide through by 3
a = 8
Therefore the number is 8
For this case we have an equation of the form:
y = A (b) ^ t
Where,
A: initial amount
b: decrease rate
t: time
Substituting values:
y = 750 (0.5) ^ ((1/15) * t)
The number of days to reach 68 mg is:
68 = 750 (0.5) ^ ((1/15) * t)
Clearing t:
(0.5) ^ ((1/15) * t) = (68/750)
log0.5 ((0.5) ^ ((1/15) * t)) = log0.5 (68/750)
(1/15) * t = log0.5 (68/750)
t = 15 * log0.5 (68/750)
t = 51.94
Rounding:
t = 52 days
Answer:
D. ≈ 52 days
