Answer:
P(XX) = 69/190
Step-by-step explanation:
Given:
20 balls, 10R, 3B, 7W.
Two taken without replacement.
Find probability of two identical colours.
P(XX)
Solution:
We use the multiplication rule for the probability of each of the 2 draws
P(RR) = 10/20*9/19 = 90/380
P(BB) = 3/20*2/19 = 6/380
P(WW) = 7/20*6/19 = 42/380
Probability of drawing two identical coloured balls
P(XX) = (90+6+42)/380 = 138/380 = 69/190
Answer:
475
Step-by-step explanation:
To find the cost of the bench, subtract 99 from 1049, then divide by 2. Add 99 to the answer(475) to get the cost of the garden table(574).
Answer:
each answer is written below
Step-by-step explanation
Answer:
r = 2 units
Step-by-step explanation:
Radius of a circle is 1/2 its diameter.
Given the diameter of circle as 4 units ,
radius r = 1/2 x 4
= 4/2
= 2 units
Call the two equations above A and B, in order to not confuse them.
A: -2x + 6y = -38
B: 3x - 4y = 32
For this system we have opposites in x and y, so Elimination (or Linear Combination) works best. Either variable works, so let's work with x first and multiply A by 3 and B by 2. This is done so we get opposites in A and B then when added together give zero.
-2x + 6y = -38 ------> multiply by 3 ----> -6x + 18y = -114
3x - 4y = 32 ------> multiply by 2 -----> 6x - 8y = 64
Now we add the new equations. The -6x and 6x are opposites and go away. We are left with
10y = -50. We divide both sides by 10 and get that y = -5.
Now we take y = -5 and put it into an original equation. Let's use A.
-2x + 6y = -38 the original equation A
-2x + 6(-5) = -38 we found y = -5
-2x + (-30) = -38 evaluating and multiplying
-2x - 30 = -38 apply the parentheses
-2x = -8 add 30 to both sides
x = 4 divide on both sides by -2
Thus x = 4 and y = -5, or (4, -5) is the solution.
