-7.8 + 4.2 - 6.5 What is the value of the expression below?

At the local grocer, the prices for apples are the following: 9 ounces for $1.89 or 1 pound for $2.49. How much will you save pe

Trava [24]

Answer: Option 'A' is correct.

Explanation:

Cost of 9 ounces of apples = $1.89

Cost of 1 ounce of apple is given by

$\frac{1.89}{9}=\$0.21$

Now, if he bought 1 pound of apple,

Cost of 1 pound of apple = $2.49

Cost of 16 ounces = $2.49

(∵ 1 pound = 16 ounces)

Cost of 1 ounce of apple is given by

$\frac{2.49}{16}=\$0.156$

So, Second option is the least expensive if he bought 1 pound of apple for $2.49

Then, he will save which is given by

$0.21-0.156=0.054\times 16=$0.87\ per pound$

Hence, option 'A' is correct.

7 0

3 years ago

Read 2 more answers

Line K has a slope of 3. Line J is perpendicular to like K and passes through the point (3,8). Type the equation of the line in

hichkok12 [17]

I'm assuming you are finding the equation of the line of Line J

Slope-intercept form: y = mx + b

[m is the slope, b is the y-intercept or the y value when x = 0 --> (0, y) or the point where the line crosses through the y-axis]

For lines to be perpendicular, the slopes have to be negative reciprocals of each other. (basically changing the sign (+/-) and flipping the fraction/switching the numerator and the denominator)

For example:

slope = 2 or $\frac{2}{1}$

Perpendicular line's slope = $-\frac{1}{2}$ [changed sign from + to -, and flipped the fraction]

slope = $-\frac{2}{5}$

Perpendicular line's slope = $\frac{5}{2}$ [changed sign from - to +, and flipped the fraction]

Since you know the slope is 3, the perpendicular line's slope is $-\frac{1}{3}$ . Plug this into the equation

y = mx + b

$y=-\frac{1}{3} x+b$ To find b, plug in the point (3, 8)

$8=-\frac{1}{3}(3)+b$

8 = -1 + b Add 1 on both sides to get "b" by itself

8 + 1 = -1 + 1 + b

9 = b

$y=-\frac{1}{3} x+9$

8 0

3 years ago

Which value is equivalent to 2 x 3 + 4 -

Kisachek [45]

D. Always do multiplication first. 2×3 is 6, and 6+4 is 10.

6 0

3 years ago

Two independent samples of sizes 20 and 30 are randomly selected from two normally distributed populations. Assume that the popu

aleksley [76]

Answer:

b. Student-t with 48 degrees of freedom

Step-by-step explanation:

For this case we need to use a Two Sample t Test: equal variances.

Assumptions

When running a two-sample equal-variance t-test, the basic assumptions are "that the distributions of the two populations are normal, and that the variances of the two distributions are the same".

Let $\bar x$ and $\bar y$ be the sample means of two sets of data of size $n_x$ and $n_y$ respectively. We assume that the distribution's of x and y are:

$x \sim N(\mu_x ,\sigma_x =\sigma)$

$y \sim N(\mu_y ,\sigma_y=\sigma)$

Both are normally distributed but without the variance equal for both populations.

The system of hypothesis can be:

Null hypothesis: $\mu_x =\mu_y$

Alternative hypothesis: $\mu_x \neq \mu_y$

We can define the following random variable:

$t=\frac{(\bar x -\bar y)-(\mu_x -\mu_y)}{s\sqrt{\frac{1}{n_x}+\frac{1}{n_y}}}$

The random variable t is distributed $t \sim t_{n_x +n_y -2}$ , with the degrees of freedom $df=n_x +n_y -2= 20+30-2=48$

And the pooled variance can be founded with the following formula:

$s^2=\frac{(n_x -1)s_x^2 +(n_y-1)s_y^2}{n_x +n_y -2}$

So on this case the best answer would be :

b. Student-t with 48 degrees of freedom

5 0

3 years ago

In one day, there are two high tides and two low tides in equally spaced intervals. The high tide is observed to be 6 feet above

creativ13 [48]

Answer: The "independent variable" is the "time" (in hours) that is plotted on the "x-axis". Note the "time" (in hours) can be "manipulated" in the sense that is it "chosen" by the humans who are measuring the data (e.g. when to start, how many hours, and at what intervals.

The "dependent variable" is the measurement (in feet) above or below the sea level, and this is plotted on the "y-axis". These values cannot be "manipulated" in the sense that one cannot "choose" what value or measurement the tide level would be at any particular time.

Hope these answers—and explanations—are of help to you.
Best wishes!

3 0

4 years ago