See https://web2.0calc.com/questions/help_29603.
Answer:
6.7% of children who finished the race in under 45 seconds.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 75 seconds
Standard Deviation, σ = 20 seconds
We are given that the distribution of time of completion is a bell shaped distribution that is a normal distribution.
Formula:
P(finished the race in under 45 seconds.)
P(x < 45)
Calculation the value from standard normal z table, we have,

6.7% of children who finished the race in under 45 seconds.
Decimal division is super easy, let me show you how.
First, let's remove the decimal from both numbers. We have <em>184 </em>and <em>340</em>. Now let's multiply those two numbers.
184*340 = 62560.
Now, we need to figure out how many decimal places are in the original decimals. 18.<u>4</u> has one decimal place, and 3.<u>4</u> has one decimal place. (We don't count zeros at the end of a decimal as a decimal place.)
Now that we've figured out that there was a total of two decimal places, there can only be two decimal places in the answer. Let's take the 62560 that we got, and put a decimal in it. Remember, only two decimal places.
If there's only two decimal places in 62560, it would look like this: 62.<u>56</u> (<em>Remember, zeros at the end of a decimal does not count as a decimal place!)</em>
There's your final answer. 62.56.
Hope this explanation helped you out. :)
Answer:
(x + 4)(2x - 3)
Step-by-step explanation:
Given
f(x) = 2x² + 5x - 12
Consider the factors of the product of the x² term and the constant term which sum to give the coefficient of the x- term.
product = 2 × -12 = - 24 and sum = + 5
The factors are + 8 and - 3
Use these factors to split the x- term
2x² + 8x - 3x - 12 ( factor the first/second and third/fourth terms )
2x(x + 4) - 3(x + 4) ← factor out (x + 4) from each term
(x + 4)(2x - 3)
Thus
f(x) = 2x² + 5x - 12 = (x + 4)(2x - 3) ← in factored form