Given nth term of an AP = 7-4n
Put n = 1 then t1 = 7-4(1) = 7-4 = 3
Put n = 2 then t2 =7-4(2) = 7-8 = -1
Common difference = t2-t1 = -1-3 = -4
9c + 4 = -23
9c = -27
c = -3
Answer:
7 13
Step-by-step explanation:
Answer:
make y the subject first
Step-by-step explanation:
y=5/7(x) -27/7
parallel lines have equal gradient m1=m2
y-y1=m(x-x1)
y-(-3)=5/7(x-4))
y=5/7(x) -20/7 -3
final answer
y=5/7(x) -41/7
Answer:
(a) P(X = 18) = 0.25
(b) P(X > 18) = 0.53
(c) P(X ≤ 18) = 0.47
(d) Mean = 19.76
(e) Variance = 22.2824
(f) Standard deviation = 4.7204
Step-by-step explanation:
We are given that discrete random variable X has the following probability distribution:
X P (x) X * P(x)
* P(x)
13 0.22 2.86 169 37.18
18 0.25 4.5 324 81
20 0.20 4 400 80
24 0.17 4.08 576 97.92
27 0.16 4.32 729 116.64
(a) P ( X = 18) = P(x) corresponding to X = 18 i.e. 0.25
Therefore, P(X = 18) = 0.25
(b) P(X > 18) = 1 - P(X = 18) - P(X = 13) = 1 - 0.25 - 0.22 = 0.53
(c) P(X <= 18) = P(X = 13) + P(X = 18) = 0.22 + 0.25 = 0.47
(d) Mean of X,
= ∑X * P(x) ÷ ∑P(x) = (2.86 + 4.5 + 4 + 4.08 + 4.32) ÷ 1
= 19.76
(e) Variance of X,
= ∑
* P(x) -
= 412.74 -
= 22.2824
(f) Standard deviation of X,
=
=
= 4.7204 .