1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
melomori [17]
3 years ago
15

A necklace and earrings cost $144. Six necklaces and five pairs of earrings cost $825

Mathematics
1 answer:
hram777 [196]3 years ago
6 0

Step-by-step explanation:

let necklace : x

let earrings : y

x+y=144 -1st eqn

6x+5y=825 -2nd eqn

y=144-X -3rd eqn

substitute eqn into 2nd eqn

6x+5(144-x)= 825

6x +720-5X =825 (expanded)

X = 825-720

X =105

substitute "X=105" into 1st eqn

(105)+y=144

y= 144-105

y=39

1 necklace = 105$

1 pair of earrings = 39$

(to check back: substitute the value into the original eqn)

You might be interested in
For a fair coin, suppose you toss the coin 100 times.
Natasha_Volkova [10]

Using the normal distribution, it is found that there is a 0.0005 = 0.05% probability of getting more than 66 heads.

<h3>Normal Probability Distribution</h3>

The z-score of a measure X of a normally distributed variable with mean \mu and standard deviation \sigma is given by:

Z = \frac{X - \mu}{\sigma}

  • The z-score measures how many standard deviations the measure is above or below the mean.
  • Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X.
  • The binomial distribution is the probability of x successes on n trials, with p probability of a success on each trial. It can be approximated to the normal distribution with \mu = np, \sigma = \sqrt{np(1-p)}.

For the binomial distribution, the parameters are given as follows:

n = 100, p = 0.5.

Hence the mean and the standard deviation of the approximation are given as follows:

  • \mu = np = 100(0.5) = 50.
  • \sigma = \sqrt{np(1-p)} = \sqrt{100(0.5)(0.5)} = 5

Using continuity correction, the probability of getting more than 66 heads is P(X > 66 + 0.5) = P(X > 66.5), which is <u>one subtracted by the p-value of Z when X = 66.5</u>.

Z = \frac{X - \mu}{\sigma}

Z = \frac{66.5 - 50}{5}

Z = 3.3

Z = 3.3 has a p-value of 0.9995.

1 - 0.9995 = 0.0005.

0.0005 = 0.05%

More can be learned about the normal distribution at brainly.com/question/4079902

#SPJ1

6 0
2 years ago
June mad 10 origami birds in 30 minutes Dylan made 4 origami birds in 10 minutes who was faster
Hitman42 [59]

Answer:

Dylan

Step-by-step explanation:

Rate of Origami Making

1) June

= 10/30

= 1/3 origami birds per minute

2) Dylan

= 4/10

= 2/5 origami birds per minute

2/5 > 1/3

So Dylan was faster.

8 0
2 years ago
If a=2,b=-1,c=-3 and d=-2.find the value of 7a2-3ac+d2​
hram777 [196]

Answer:

42

Step-by-step explanation:

It's just a distribution property where the given value of each variables (a, b, c, d) are being distributed to the given equation:

7a2-3ac+d2

7(2)(2) - 3(2)(-3) + (-2)(2)

28 + 18 - 4 = 42

3 0
3 years ago
The function. In the graph is f(x) =
Tanya [424]

Answer:

x^3-2x^2-5x+6

Step-by-step explanation:

We have been given a graph of the function f(x).

Now we need to use that graph to find the equation of the graph and match with the correct choice from the give choices:

x^4-2x^2+5x+6

x^3-2x^2-5x+6

x^3-2x^2+5x+6

-x^4-2x^2+5x+6

We see that graph has end points in opposite direction then the degree of polynomial must be ODD.

Available degrees are 3 and 4. Degree 3 is odd so it is choice B or C.

Only x^3-2x^2-5x+6 satisfies the given points from graph.

Hence correct choice is x^3-2x^2-5x+6.

4 0
3 years ago
If in a game of glass stepping stones. there are 18 tiles of glass. two in each row. one is tempered and will be fine if you jum
Julli [10]
There chance for just getting across each row would be 50% but there chance of getting across completely is 1 in 18
4 0
2 years ago
Other questions:
  • J ={x | x is an integer and x&gt;2}<br> J=?
    7·1 answer
  • In four rounds of a card game, you get scores of -1,-4,-8, and 10. What is your score ?
    6·1 answer
  • The cost before tax for an order of CDs from Music &amp; More store was $211.60. If the store ordered 20 equally priced
    7·2 answers
  • Can anyone explain how to do this???
    7·2 answers
  • Two trains travel at right angles to each other after leaving the same train station at the same time. Two hours later they are
    12·1 answer
  • 4(x-2)=2(x - 4) + 2x
    9·1 answer
  • Steve earned a 96% on his first math test, a 74% on his second test, and a 85% on his third test. What is his test average?
    5·1 answer
  • Find the missing length indicated
    9·1 answer
  • Please help me, I don't know the difference between an expression and an equation. XD
    9·1 answer
  • The equation of the trend line shown is = − 20/9 + 900. Use the trend line to predict the number of minutes it will take Mrs. Th
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!