Answer:
0.865
Step-by-step explanation:
To solve for the probability we would be using the formula:
F(x) = 1 - e^−λx
Therefore, P(x > 2000) = F(x) = 1 - e^−λx
Mean = 1000 hours
λ = 1/mean = 1/1000 hours
x= 2000 hours
F(x) = 1 - e^−(1/1000)2000
F(x) = 1 - e^−2
= 0.8646647168
Therefore, the probability the the circuit will last at least 2000 hours = 0.865
Answer:

Step-by-step explanation:

Divide both sides by 7:

Subtract 4 from both sides:

Answer: "Count 2 and then count 31 more."
Step-by-step explanation:
We have the equation:
231 - 198
Now, the negative number is kinda ugly, so i will write it as:
200 - 2 = 198
Is a lot easier work with 200 and 2, than with 198.
Then the equation is now:
231 - (200 - 2)
And the left number we also have a "200", so it can be written as:
200 + 31 = 231
As this is a sum, we can ignore the parentheses.
200 + 31 - 200 + 2
31 + 2
Then the correct option is:
"Count 2 and then count 31 more."
Answer:
C −2a^3+9a^2+45a+6ab^2+18b^2
Step-by-step explanation:
(a+3) ( −2a^2+15a+6b^2)
Distribute the a to the large term in parentheses and the 3 to the large term in parentheses
a ( −2a^2+15a+6b^2)+3 ( −2a^2+15a+6b^2)
−2a^3+15a^2+6ab^2 −6a^2+45a+18b^2
Combine like terms
−2a^3+15a^2−6a^2+6ab^2 +45a+18b^2
-2 a^3 + 9 a^2 + 6 a b^2 + 45 a + 18 b^2
Answer:
yes
Step-by-step explanation:
note that 20% =
= 
Hence to find 20% of a number, dividing the number by 5 is correct
20% of £30 =
= £6