B I hope it helps for you
Answer: 12 friends.
Step-by-step explanation:
the data we have is:
Mei Su had 80 coins.
She gave the coins to her friends, in such a way that every friend got a different number of coins, then we have that:
The maximum number of friends that could have coins is when:
friend 1 got 1 coin
friend 2 got 2 coins
friend 3 got 3 coins
friend N got N coins
in such a way that:
(1 + 2 + 3 + ... + N) ≥ 79
I use 79 because "she gave most of the coins", not all.
We want to find the maximum possible N.
Then let's calculate:
1 + 2 + 3 + 4 + 5 = 15
15 + 6 + 7 + 8 + 9 + 10 = 55
now we are close, lets add by one number:
55 + 11 = 66
66 + 12 = 78
now, we can not add more because we will have a number larger than 80.
Then we have N = 12
This means that the maximum number of friends is 12.
Answer:
Part 1) The explanatory variable is the type of oven
It is a categorical variable
Part 2) The response variable is the baking time
It is a quantitative variable
part 3) two-sample z-test for proportions should be used for the test
Step-by-step explanation:
An explanatory variable is an independent variable that is not affected by all other variables. In this experiment, the type of oven is the input variable and it is not affected by any other variable
A categorical variable is one that has two or more categories without any intrinsic ordering of the categories. The type of oven is either gas or electric, so it is categorical.
A response variable is a dependent variable whose variation depends on other variables. The baking time in this experiment depends on the type of oven used
A quantitative variable is one that take on numerical values.
A two proportion z-test allows you to compare two proportions to see if they are the same. The null hypothesis (H0) for the test is that the proportions are the same. The alternate hypothesis (H1) is that the proportions are not the same.
The dimensions of the garden that will require the least amount of fencing are 450 m and 900 m and the perimeter of the area is 1800 m.
<h3>What is the area of the rectangle?</h3>
It is defined as the area occupied by the rectangle in two-dimensional planner geometry.
The area of a rectangle can be calculated using the following formula:
Rectangle area = length x width
Let's suppose x and y are the sides of the rectangular garden and y is the parallel to the river.
Then according to the problem:
2x + y = P ..(1)
P is the perimeter of the rectangle.
xy = 405000 (area of the rectangle)
Plug the value of y in the equation (1) from the above equation.
P(x) = 2x + 405000/x
P'(x) = x—405000/x² = 0
x = 450 m
P''(x) > 0 hence at x = 450 the value of P(x) is minimum.
y = 405000/450
y = 900 m
P(min) = 1800 m
Thus, the dimensions of the garden that will require the least amount of fencing are 450 m and 900 m and the perimeter of the area is 1800 m.
Learn more about the rectangle here:
brainly.com/question/15019502
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