Answer:
a : b = 19 : 7
Step-by-step explanation:
Given
4a - 5b : 5a + 4b = 1 : 3
Expressing in fractional form, that is
= ( cross- multiply )
3(4a - 5b) = 5a + 4b ← distribute left side
12a - 15b = 5a + 4b ( subtract 5a from both sides )
7a - 15b = 4b ( add 15b to both sides )
7a = 19b ( divide both sides by 7 )
a = b ( divide both sides by b )
=
That is a : b = 19 : 7
Answer:55.227
Step-by-step explanation:
Given data
mass =13lb
spring stretches by =4.5in=0.375 ft
g=
Now Spring constant K
mg=kx
k=
For critical damping
and
substituting values
c=55.227 lb.sec/ft
Multiply the area of all sides (10*5)*2+(10*4)*2+(4*5)*2 to get 220 in^2
This is a binomial distribution problem. The formula to find the required probability is:
p(X) = [ n! / ((n - X)! · X!) ] · (p)ˣ <span>· (q)ⁿ⁻ˣ
where:
X = number of what you are trying to find the probability for = 20 or 21;
n = number of events randomly selected = 21;
p = probabiity of sucess = 0.9 (90%);
q = probability of failure = 0.1 (10%);
We need to find the probability of two events: finding 20 students and finding 21 students. Therefore P(X) = P(X = 20) + P(X = 21).
P(X = 20) = </span> [ 21! / ((21 - 20)! · 20!) ] · (0.9)²⁰ <span>· (0.1)²¹⁻²⁰
= 0.2553
P(X = 21) = [ 21! / ((21 - 21)! </span>· 21!) ] · (0.9)²¹ <span>· (0.1)²¹⁻²¹
= 0.1094
Therefore:
P(X) = 0.2553 + 0.1094 = 0.3647
We have a probability of 36.5% to find 20 or more students </span><span>who consider calculus to be an exciting subject.</span>
Since the fencing is on the outside of the rectangle you would find the perimeter so 80 + 80+ 45+ 45 which equals 250 feet!