All categories

3 years ago

Mike built a model of a 42 ft building using a scale of 2 cm = 3 ft. What is the height of the model?

1 answer:

5 0

Ok so important numbers 42 ft, 2cm, 3 ft and lets take height as x

if 2cm=3ft than x cm= 42 ft
2 = 3
-------
x= 42
cross multiply divide
(42)2/3
84/3
28

You might be interested in

At noon, a submarine was located at 5 12 meters below

Cerrena [4.2K]

-512 is the answer because 512 is a negative solution in Integers math

7 0

3 years ago

What is the value of r?

finlep [7]

Answer:

A.12

Step-by-step explanation:

2×r-13 = 11

r + 2 = 14

11 + 14 = 25

3 0

3 years ago

I will mark brainlist for this science question please. I need to figure out where to put where. And what percentages. Your choi

ozzi

Answer:

Long wings: 0

Short wings: 100

Step-by-step explanation:

Genotype of the flies: ww

The cross will yield the genotype ww and the flies will express the recessive phenotype which is short wings.

The probability for long wings will be 0 as there is no dominant allele present. The probability for short wings will be 100 as all the flies will have short wings.

Hope that helps.

3 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:

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

Now we calculate the F statistic as:

$F=MSB/MSE=172/23.78=7.23$

The degrees of freedom of the numerator are:

$dfn=a-1=3-1=2$

The degrees of freedom of the denominator are:

$dfd=N-a=3*4-3=12-3=9$

The P-value of F=7.23, dfn=2 and dfd=9 is:

$P-value=P(F>7.23)=0.01342$

As the P-value (0.013) is smaller than the significance level (0.05), the null hypothesis is rejected.

There is evidence to support the claim that there is a difference in the ability of the brands to absorb water.

3 0

3 years ago

Twelve more than half of a number is equal to the number

tester [92]

Let's consider that number to be 'x'..
So, twice the number (2x) is 12 greater than than the half of the number.
So the equation will be like,
2x=12+x/2
Solving this further,
2x=(24+x)/2
=> 4x=24+x
=>4x-x=24
=>3x=24
=>x=8..
So the number is "8".

5 0

2 years ago