The standard deviation of a particular sample is equal to the standard deviation divided by the square root of the sample size. That is,

The mean of a particular sample is equal to the mean of the set the sample was taken from. That is,

(3+6X(5+4)÷3-7) the answer is 14
The multiplication of −2(−5)(−3) is -30
The multiplication of numbers in brackets with negative signs takes a method whereby the signs are taken into account when performing the arithmetic operation.
From the given question, we are to multiply:
= - 2 × (-5) × (-3)
= +10 × (-3)
= -30
Learn more about the multiplication of numbers here:
brainly.com/question/1755985
Answer:
Step-by-step explanation:
Find the amount of time it takes for a beam of light from the Sun to reach Earth.
First of all we can draw a parallel line to divide the figure into a triangle and a rectangle as shown in the figure. To find the area of our rectangle, remember that the area of a rectangle is length times width, so

. Since we know for our figure that the length and width of our rectangle are 13cm and 6cm respectively, lets replace those values in our formula to get its area:


Similarly, the area of a triangle is one half times base times height, so

. Since we know that our base is 8cm and our height 6cm, lets replace those values in our equation to find the area of our triangle:


Now the only thing left is add our areas:

We can conclude that the correct answer is <span>
A. 102</span>