All categories

3 years ago

Subtract 4/5 - 4/7

Mathematics

1 answer:

Bumek [7]3 years ago

6 0

Answer: 4/5 - 4/7 = 8/35

Step-by-step explanation:

You might be interested in

Many experts have argued for the elimination of rote memorization as a method for learning mathematical facts such as basic oper

N76 [4]

I think they should keep it around, even if it might not be the most efficient strategy. After all, what if you need to solve a problem using multiple strategies?

5 0

2 years ago

Calculate the trade discount for 3030 boxes of computer paper if the unit price is $14.9314.93 and a single trade discount rate

zhannawk [14.2K]

Answer:

Total trade discount on 30 boxes = $201.555

Step-by-step explanation:

1 box = $14.93

And a trade discount of 45% is allowed on a single box,

Therefore, the discount on one $14.93 box will be

45% × $14.93 = $6.7185

So, if there are now 30 boxes, the trade discount on all 30 boxes will be

30 × (trade discount on one box) = 30 × ($6.7185) = $201.555

Hope this helps!

5 0

2 years ago

Expand this expression (x-y)²

pochemuha

Answer:

x^2 - 2xy + y^2.

Step-by-step explanation:

(x - y)^2

= (x - y)(x - y)

= x(x -y) - y(x - y)

= x^2 - xy - xy + y^2

= x^2 - 2xy + y^2.

8 0

2 years ago

In a completely randomized experimental design, three brands of paper towels were tested for their ability to absorb water. Equa

arlik [135]

Answer:

Yes. At this significance level, there is evidence to support the claim that there is a difference in the ability of the brands to absorb water.

Step-by-step explanation:

The question is incomplete:

The significance level is 0.05.

The data is:

Brand X: 91, 100, 88, 89

Brand Y: 99, 96, 94, 99

Brand Z: 83, 88, 89, 76

We have to check if there is a significant difference between the absorbency rating of each brand.

Null hypothesis: all means are equal

$H_0:\mu_x=\mu_y=\mu_z$

Alternative hypothesis: the means are not equal

$H_a: \mu_x\neq\mu_y\neq\mu_z$

We have to apply a one-way ANOVA

We start by calculating the standard deviation for each brand:

$s_x^2=30,\,\,s_y^2=6,\,\,s_z^2=35.33$

Then, we calculate the mean standard error (MSE):

$MSE=(\sum s_i^2)/a=(30+6+35.33)/3=71.33/3=23.78$

Now, we calculate the mean square between (MSB), but we previously have to know the sample means and the mean of the sample means:

$M_x=92,\,\,M_y=97,\,\,M_z=84\\\\M=(92+97+84)/3=91$

The MSB is then:

$s^2=\dfrac{\sum(M_i-M)^2}{N-1}\\\\\\s^2=\dfrac{(92-91)^2+(97-91)^2+(84-91)^2}{3-1}\\\\\\s^2=\dfrac{1+36+49}{2}=\dfrac{86}{2}=43\\\\\\\\MSB=ns^2=4*43=172$