All categories

2 years ago

In △BFD, m∠B = 34 ° and m∠FDC = 76°. What is m∠F and m∠FDB?

Mathematics

2 answers:

Paul [167]2 years ago

7 0

Answer:

f=42

fdb=104

Step-by-step explanation:

Ket [755]2 years ago

5 0

Answer:

the answer to this question is 42, and 104

Step-by-step explanation:

Hope this help you :)

You might be interested in

Express this number in scientific notation.<br> 0.00061

shutvik [7]

Answer:

6.1×10^-4

___________________

7 0

3 years ago

In a process that manufactures bearings, 90% of the bearings meet a thickness specification. A shipment contains 500 bearings. A

Marina86 [1]

Answer:

(a) 0.94

(b) 0.20

Step-by-step explanation:

From a population (Bernoulli population), 90% of the bearings meet a thickness specification, let $p_1$ be the probability that a bearing meets the specification.

So, $p_1=0.9$

Sample size, $n_1=500$ , is large.

Let X represent the number of acceptable bearing.

Convert this to a normal distribution,

Mean: $\mu_1=n_1p_1=500\times0.9=450$

Variance: $\sigma_1^2=n_1p_1(1-p_1)=500\times0.9\times0.1=45$

$\Rightarrow \sigma_1 =\sqrt{45}=6.71$

(a) A shipment is acceptable if at least 440 of the 500 bearings meet the specification.

So, $X\geq 440.$

Here, 440 is included, so, by using the continuity correction, take x=439.5 to compute z score for the normal distribution.

$z=\frac{x-\mu}{\sigma}=\frac{339.5-450}{6.71}=-1.56$ .

So, the probability that a given shipment is acceptable is

$P(z\geq-1.56)=\int_{-1.56}^{\infty}\frac{1}{\sqrt{2\pi}}e^{\frac{-z^2}{2}}=0.94062$

Hence, the probability that a given shipment is acceptable is 0.94.

(b) We have the probability of acceptability of one shipment 0.94, which is same for each shipment, so here the number of shipments is a Binomial population.

Denote the probability od acceptance of a shipment by $p_2$ .

$p_2=0.94$

The total number of shipment, i.e sample size, $n_2= 300$

Here, the sample size is sufficiently large to approximate it as a normal distribution, for which mean, $\mu_2$ , and variance, $\sigma_2^2$ .

Mean: $\mu_2=n_2p_2=300\times0.94=282$

Variance: $\sigma_2^2=n_2p_2(1-p_2)=300\times0.94(1-0.94)=16.92$

$\Rightarrow \sigma_2=\sqrt(16.92}=4.11$ .

In this case, X>285, so, by using the continuity correction, take x=285.5 to compute z score for the normal distribution.

$z=\frac{x-\mu}{\sigma}=\frac{285.5-282}{4.11}=0.85$ .

So, the probability that a given shipment is acceptable is

$P(z\geq0.85)=\int_{0.85}^{\infty}\frac{1}{\sqrt{2\pi}}e^{\frac{-z^2}{2}=0.1977$

Hence, the probability that a given shipment is acceptable is 0.20.

(c) For the acceptance of 99% shipment of in the total shipment of 300 (sample size).

The area right to the z-score=0.99

and the area left to the z-score is 1-0.99=0.001.

For this value, the value of z-score is -3.09 (from the z-score table)

Let, $\alpha$ be the required probability of acceptance of one shipment.

So,

$-3.09=\frac{285.5-300\alpha}{\sqrt{300 \alpha(1-\alpha)}}$

On solving

$\alpha= 0.977896$

Again, the probability of acceptance of one shipment, $\alpha$ , depends on the probability of meeting the thickness specification of one bearing.

For this case,

The area right to the z-score=0.97790

and the area left to the z-score is 1-0.97790=0.0221.

The value of z-score is -2.01 (from the z-score table)

Let $p$ be the probability that one bearing meets the specification. So

$-2.01=\frac{439.5-500 p}{\sqrt{500 p(1-p)}}$

On solving

$p=0.9053$

Hence, 90.53% of the bearings meet a thickness specification so that 99% of the shipments are acceptable.

8 0

3 years ago

What is the definition of A net (of a shape)

Hatshy [7]

Answer: A pure mathematics internet could be a 2-dimensional form that may be rolled-up to make a three-d form or a solid. Or a internet could be a pattern created once the surface of a solid figure is ordered out flat showing every face of the figure. A solid could have totally different nets.

Step-by-step explanation: A pure mathematics web could be a 2-dimensional form which will be closed to make a third-dimensional form or a solid. Or a web could be a pattern created once the surface of a solid figure is arranged out flat showing every face of the figure. A solid could have completely different nets.

6 0

3 years ago

Read 2 more answers

I need help with this question. can someone please help me

Ahat [919]

-2x + y =3
use 5 number and put it in above equation to find y, I will use -2,-1,0,1,2
x y
-2 -1
-1 1
0 3
1 5
2 7

Then draw the graph, find another point in the graph which intersect the slope,
lets say i found (-3,-3)which is on the slope
to prove it, i put (-3,-3) in the equation -2x + y = 3
and i got
3 = 3
Thus it is correct.

7 0

3 years ago

What can you do to a 3 to make it a 7, besides just adding 4?

olchik [2.2K]

Answer:

multiply 3 by 2 and add 1 to get 7

Step-by-step explanation:

3x2+1=7

4 0

3 years ago

Read 2 more answers