Ask question

Ask question

All categories

2 years ago

5

Last year,Mark was 46 inches tall.This year,Marks height is 3 inches less than peters height.Peter is 51 inches tall.How tall is

mark?
Write an equation to represent the situation.
Then solve the equation to answer the problem.

2 answers:

In-s [12.5K]2 years ago

7 0

Im not sure abbout the equations... but Mark is 48 inches, cuz it says; He WAS 46 in. tall. this year, amrks height is 3 inches LESS than peters height. So now, peter is 51 in. tall How tall is mark NOW? So u just have to minus 51-3 = 48!

zvonat [6]2 years ago

4 0

I think the equation is 51-3=49

You might be interested in

Li wants to add these items to her suitcase: a hairdryer (1.25 lb), a hand-held video game (0.6 lb), an extra video game (0.25 l

lbvjy [14]

Add some of them or all of them to your sum of 47.75, if either or exceeds the limit then that is what left out.

7 0

2 years ago

Read 2 more answers

PLEASE HELP ME!

algol13

Step-by-step explanation:

$1.\sum_{i=1}^{5}3i$

The simplest method is "brute force". Calculate each term and add them up.

∑ = 3(1) + 3(2) + 3(3) + 3(4) + 3(5)

∑ = 3 + 6 + 9 + 12 + 15

∑ = 45

$2.\sum_{k=1}^{4}(2k)^{2}$

∑ = (2×1)² + (2×2)² + (2×3)² + (2×4)²

∑ = 4 + 16 + 36 + 64

∑ = 120

$3.\sum_{k=3}^{6}(2k-10)$

∑ = (2×3−10) + (2×4−10) + (2×5−10) + (2×6−10)

∑ = -4 + -2 + 0 + 2

∑ = -4

4. 1 + 1/4 + 1/16 + 1/64 + 1/256

This is a geometric sequence where the first term is 1 and the common ratio is 1/4. The nth term is:

a = 1 (1/4)ⁿ⁻¹

So the series is:

$\sum_{j=1}^{7}(\frac{1}{4})^{j-1}$

5. -5 + -1 + 3 + 7 + 11

This is an arithmetic sequence where the first term is -5 and the common difference is 4. The nth term is:

a = -5 + 4(n−1)

a = -5 + 4n − 4

a = 4n − 9

So the series is:

$\sum_{j=1}^{5}(4j-9)$

5 0

2 years ago

An experiment on memory was performed, in which 16 subjects were randomly assigned to one of two groups, called "Sentences" or "

FromTheMoon [43]

Answer:

There is no significant difference between the averages.

Step-by-step explanation:

Let's call

$\large X_{sentences}$ the mean of the “sentences” group

$\large S_{sentences}$ the standard deviation of the “sentences” group

$\large X_{intentional}$ the mean of the “intentional” group

$\large S_{intentional}$ the standard deviation of the “intentional” group

Then, we can calculate by using the computer

$\large X_{sentences}=28.75$

$\large S_{sentences}=3.53553$

$\large X_{intentional}=31.625$

$\large S_{intentional}=1.40788$

$\large X_{sentences}-X_{intentional}=28.75-31.625=-2.875$

The <em>standard error of the difference (of the means)</em> for a sample of size 8 is calculated with the formula

$\large \sqrt{(S_{sentences})^2/8+(S_{intentional})^2/8}$

So, the standard error of the difference is

$\large \sqrt{(3.53553)^2/8+(1.40788)^2/8}=1.34546$

<em>In order to see if there is a significant difference in the averages of the two groups, we compute the interval of confidence of 95% for the difference of the means corresponding to a level of significance of 0.05 (5%). </em>

<em>If this interval contains the zero, we can say there is no significant difference. </em>

<em>Since the sample size is small, we had better use the Student's t-distribution with 7 degrees of freedom (sample size-1), which is an approximation to the normal distribution N(0;1) for small samples. </em>

We get the $\large t_{0.05}$ which is a value of t such that the area under the Student's t distribution outside the interval $\large [-t_{0.05}, +t_{0.05}]$ is less than 0.05.

That value can be obtained either by using a table or the computer and is found to be

$\large t_{0.05}=2.365$

Now we can compute our confidence interval

$\large (X_{sentences}-X_{intentional}) \pm t_{0.05}*(standard \;error)=-2.875\pm 2.365*1.34546$

and the confidence interval is

[-6.057, 0.307]

Since the interval does contain the zero, we can say there is no significant difference in these samples.

6 0

2 years ago

sandy is observing the velocity of a runner at different times. After one hour, the velocity of the runner is 4 km/h. After two

Butoxors [25]

A) Let x stand for time, y stand for velocity.
We are given the points (2,50), (6, 54). We can make a line using the slope intercept form
y = mx + b.
slope is (54 - 50)/(6-2) = 4/4 = 1
y = 1x + b
plug in point (2,50) to find b
50 = 1(2) + b
50-2 = b
48 = b
the equation is y = 1x + 48
Make standard form.
<span>x - y = -48</span>

7 0

2 years ago

Daniel Potter bought a new car for $20,000.00. Two years later, he wanted to sell it. He was offered $14,650.00 for it. If he so

olga_2 [115]

Answer: 13.375% per year

Explanation:

1) Depreciation is the loss of value: $ 20,000.00 - $ 14,650.00 = $ 5,350

2) The percent of depreciation is amount of the depreciation divided by the value of the car when purchased, times 100.

That is (5,350 / $ 20,000) * 100 = 26.75 %

2) The rate is percent of depreciation per year:

depreciation rate = % of depreciation / number of years = 26.75% / 2 = 13.375% per year.

5 0

2 years ago

Read 2 more answers