Answer:
0.4
Step-by-step explanation:
For independent events,
P(X ∩ Y) = P(X)* P(Y)
=>
1/3 = P(X)*(5/6)
solve for P(X) =>
P(X) = (1/3)*(6/5) = 2/5 = 0.4
Depends on your grade in elementary, and when you decide to attend college after you graduate.
Answer:
-6.5
Step-by-step explanation:
Answer:
a)4080 trees
b)104 trees
Step-by-step explanation:
<u>1st - 24 trees</u>
<u>last (40th) - 180 trees</u>
If differences between any row (except 40th) and next row are equal then
<u>2nd - 24 trees+X</u>
<u>3rd - (2nd+X) or 24 trees + 2X</u>
coefficient of X is <u>number of row minus 1</u>, therefore 40th row has <u>24 trees + 39X</u>, and it is equal to <u>180</u>. We can make an equation from this:
<u>24tr+39X=180tr</u>
<u>39X=156tr</u>
<u>X=4tr</u>
By this we can find how many trees are there in the 21st, 21st row has 24 trees+20X=24 trees+80 trees=104 trees
To find how many trees are there in the whole orchard, we add them all:
<u>1st - 24 trees, 2nd - 24 trees + X, 3rd - 24 trees + 2X,</u>
easily, it is just <u>24 trees x 40 + 39X x 20 = 4080 trees</u>
