How do you find the value of x in. x+y=z

"Find the sum of the first 50 term in this sequence 4, 7, 10, 13, ...". How do i do this without writing them all out, and how d

melisa1 [442]

First term ,a=4 , common difference =4-7=-3, n =50
sum of first 50terms= (50/2)[2×4+(50-1)(-3)]
=25×[8+49]×-3
=25×57×-3
=25× -171
= -42925
derivation of the formula for the sum of n terms
Progression, S
S=a1+a2+a3+a4+...+an

S=a1+(a1+d)+(a1+2d)+(a1+3d)+...+[a1+(n−1)d] → Equation (1)

S=an+an−1+an−2+an−3+...+a1

S=an+(an−d)+(an−2d)+(an−3d)+...+[an−(n−1)d] → Equation (2)

Add Equations (1) and (2)
2S=(a1+an)+(a1+an)+(a1+an)+(a1+an)+...+(a1+an)

2S=n(a1+an)
S=n/2(a1+an)

Substitute an = a1 + (n - 1)d to the above equation, we have
S=n/2{a1+[a1+(n−1)d]}
S=n/2[2a1+(n−1)d]

5 0

3 years ago

Explain the difference between correlation and causation and what makes causation difficulty to prove?

bixtya [17]

Ausation vs. Correlation. Causation at its simplest definition refers to determining the cause or reason for some sort of phenomenon. ... A correlation is simply a recognized relationship between two things or events, but it does not implycausation. Rather, in cases of correlation, one thing or event predicts another. hope it helps

6 0

3 years ago

Help pls will give brainlist make sure to show work if needed

weqwewe [10]

Answer:

11

Step-by-step explanation:

Just make your dot plot so that the amount of dots corresponding to the number is the amount of times the number shows in the box. :)

4 0

3 years ago

The prior probabilities for events A1 and A2 are P(A1) = 0.35 and P(A2) = 0.50. It is also known that P(A1 ∩ A2) = 0. Suppose P(

forsale [732]

Answer:

Step-by-step explanation:

Hello!

Given the probabilities:

P(A₁)= 0.35

P(A₂)= 0.50

P(A₁∩A₂)= 0

P(BIA₁)= 0.20

P(BIA₂)= 0.05

a)

Two events are mutually exclusive when the occurrence of one of them prevents the occurrence of the other in one repetition of the trial, this means that both events cannot occur at the same time and therefore they'll intersection is void (and its probability zero)

Considering that P(A₁∩A₂)= 0, we can assume that both events are mutually exclusive.

b)

Considering that $P(BIA)= \frac{P(AnB)}{P(A)}$ you can clear the intersection from the formula $P(AnB)= P(B/A)*P(A)$ and apply it for the given events: