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2 years ago

What error did Maria likely make?

Mathematics

1 answer:

raketka [301]2 years ago

7 0

She didn’t notice that the 3 and the 4 both do not have the variable “n” with them
She just added up all the numbers together then added the variable at the end.

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Write an equation that represents a horizontal translation 10 units left of the graph of g(x) = |x|

Vika [28.1K]

Answer: h(x) = |x+10|

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Explanation:

To shift the graph 10 units to the left, we replace x with x+10. What's really going on is that the xy axis shifts 10 units to the right (because x is now x+10; eg, x = 2 ---> x+10 = 2+10 = 12) so it appears that the graph is moving to the left. The general rule is h(x) = g(x+10).

So,
g(x) = |x|
g(x+10) = |x+10| ... every x has been replaced with x+10
h(x) = g(x+10)
h(x) = |x+10|

We can use a graphing tool like GeoGebra to visually confirm we have the right answer (see attached). Note how a point like (0,0) on the green graph moves to (-10,0) on the red graph.

7 0

2 years ago

Read 2 more answers

A prticular type of tennis racket comes in a midsize versionand an oversize version. sixty percent of all customers at acertain

svetlana [45]

Answer:

a) P(x≥6)=0.633

b) P(4≤x≤8)=0.8989 (one standard deviation from the mean).

c) P(x≤7)=0.8328

Step-by-step explanation:

a) We can model this a binomial experiment. The probability of success p is the proportion of customers that prefer the oversize version (p=0.60).

The number of trials is n=10, as they select 10 randomly customers.

We have to calculate the probability that at least 6 out of 10 prefer the oversize version.

This can be calculated using the binomial expression:

$P(x\geq6)=\sum_{k=6}^{10}P(k)=P(6)+P(7)+P(8)+P(9)+P(10)\\\\\\P(x=6) = \binom{10}{6} p^{6}q^{4}=210*0.0467*0.0256=0.2508\\\\P(x=7) = \binom{10}{7} p^{7}q^{3}=120*0.028*0.064=0.215\\\\P(x=8) = \binom{10}{8} p^{8}q^{2}=45*0.0168*0.16=0.1209\\\\P(x=9) = \binom{10}{9} p^{9}q^{1}=10*0.0101*0.4=0.0403\\\\P(x=10) = \binom{10}{10} p^{10}q^{0}=1*0.006*1=0.006\\\\\\P(x\geq6)=0.2508+0.215+0.1209+0.0403+0.006=0.633$

b) We first have to calculate the standard deviation from the mean of the binomial distribution. This is expressed as:

$\sigma=\sqrt{np(1-p)}=\sqrt{10*0.6*0.4}=\sqrt{2.4}=1.55$

The mean of this distribution is:

$\mu=np=10*0.6=6$

As this is a discrete distribution, we have to use integer values for the random variable. We will approximate both values for the bound of the interval.

$LL=\mu-\sigma=6-1.55=4.45\approx4\\\\UL=\mu+\sigma=6+1.55=7.55\approx8$

The probability of having between 4 and 8 customers choosing the oversize version is:

$P(4\leq x\leq 8)=\sum_{k=4}^8P(k)=P(4)+P(5)+P(6)+P(7)+P(8)\\\\\\P(x=4) = \binom{10}{4} p^{4}q^{6}=210*0.1296*0.0041=0.1115\\\\P(x=5) = \binom{10}{5} p^{5}q^{5}=252*0.0778*0.0102=0.2007\\\\P(x=6) = \binom{10}{6} p^{6}q^{4}=210*0.0467*0.0256=0.2508\\\\P(x=7) = \binom{10}{7} p^{7}q^{3}=120*0.028*0.064=0.215\\\\P(x=8) = \binom{10}{8} p^{8}q^{2}=45*0.0168*0.16=0.1209\\\\\\P(4\leq x\leq 8)=0.1115+0.2007+0.2508+0.215+0.1209=0.8989$

c. The probability that all of the next ten customers who want this racket can get the version they want from current stock means that at most 7 customers pick the oversize version.

Then, we have to calculate P(x≤7). We will, for simplicity, calculate this probability substracting P(x>7) from 1.

$P(x\leq7)=1-\sum_{k=8}^{10}P(k)=1-(P(8)+P(9)+P(10))\\\\\\P(x=8) = \binom{10}{8} p^{8}q^{2}=45*0.0168*0.16=0.1209\\\\P(x=9) = \binom{10}{9} p^{9}q^{1}=10*0.0101*0.4=0.0403\\\\P(x=10) = \binom{10}{10} p^{10}q^{0}=1*0.006*1=0.006\\\\\\P(x\leq 7)=1-(0.1209+0.0403+0.006)=1-0.1672=0.8328$

7 0

2 years ago

Ellen said she spent half her money for lunch and half of what was left for a movie. She now has $1.20. How much did she spend f

goldenfox [79]

Answer: She spend $1.20 for lunch.

Step-by-step explanation:

Let the total amount be 'x'.

Half of her money spend for lunch be $\dfrac{x}{2}$

Half of her money left for a movie be $\dfrac{x}{2}$

Amount she has now = $1.20

So, According to question, it becomes ,

$\dfrac{x}{2}=1.20\\\\x=1.20\times 2\\\\x=\$2.40$

Hence, Amount she spend for lunch is $\dfrac{x}{2}=\dfrac{2.40}{2}=\$1.20$

Therefore, she spend $1.20 for lunch.

8 0

2 years ago

Nick found the quotient of 8.64 and 1.25 × 105. His work is shown below. 1. (8.64 × 101) (1.25 × 105) 2. (8.64 1.25 ) (101 105 )

Savatey [412]

Answer:

B.) No, the power multiplied to 8.64 should have an exponent of 0.

Step-by-step explanation:

took the test on Edgenuity and got it right! Hope this helps and please mark brainliest if can.

4 0

1 year ago

Read 2 more answers

Jenny is taking a vacation to Florida. She travels 70 kilometers per hour for 2 hours, and 63 kilometers per hour for 5 hours. O

Helga [31]

Jenny traveled 70 km/h over 2 hours and 63 km/h over 5 hours. Her travel time was a total of 7 hours.

We need to find out how far she traveled during this 7-hour period.

70 km/h * 2 h = 140 km
63 km/h * 5 h = 315 km

Then, we can add 140 km and 315 km to get a total distance traveled of <em>455 km/h.</em>

We were asked to find the average <em>speed.</em> We can find it now, since we have total distance traveled (455 km) and total time taken (7 hours).

Then,
455km / 7h = 65 km/h.

6 0

2 years ago