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
faust18 [17]
4 years ago
14

jerry has 60 coins consisting of quarters and dimes. The coins combined value is $9.45. Find out how are quarters and how many a

re dimes.
Mathematics
1 answer:
jekas [21]4 years ago
7 0
Eq. 1 .10x + .25y = 9.45
Eq. 2 x + y = 60 rewrite as x = 60 - y and substitute into equation 1.

.10(60 - y) + .25y = 9.45
6 - .1y + .25y = 9.45
6 + .15y = 9.45
.15y = 3.45
y = 23
60 - 23 = 37

23 quarters
37 dimes


23* .25 = 5.75
37 * .1 = 3.70
5.75 + 3.70 =9.45
You might be interested in
What is 15% off of $24.00
marshall27 [118]

Answer:

$20.40

Step-by-step explanation:

15 percent of 24 = 3.6

24 - 3.6 = 20.4

= $20.40

8 0
3 years ago
In how many ways can 12 people be chosen from a group of 20
Alika [10]

Answer:0 ways

Step-by-step explanation:

6 0
3 years ago
which linear system has been correctly solved for one of the variables from the following system? 2x - y = -1 2x y = -7 2x - y =
mr Goodwill [35]
If you would like to solve the system of linear equations, you can do this using the following steps:

2x - y = -1 ... y = 2x + 1
2x + y = -7 ... y = -7 - 2x

The correct result would be: y = 2x + 1, <span>2x + y = -7.</span>
4 0
4 years ago
If you want another good app for math I suggest Conects
Elodia [21]
Thank you so much for the tip
4 0
3 years ago
The manager of a warehouse would like to know how many errors are made when a product’s serial number is read by a bar-code read
Firlakuza [10]

Answer:

The mean and standard deviation changed to 23.5 and 14.62 respectively, based on all 12 samples.

Step-by-step explanation:

We are given that the Six samples are collected of the number of scanning errors: 36, 14, 21, 39, 11, and 2 errors, per 1,000 scans each.

Representing the data in tabular form;

           X                            X - \bar X                            (X - \bar X)^{2}

          36                     36 - 20.5 = 15.5                   240.25

          14                      14 - 20.5 = -6.5                     42.25  

          21                       21 - 20.5 = 0.5                      0.25

          39                      39 - 20.5 = 18.5                   342.25

           11                        11 - 20.5 = -9.5                     90.25

           2                         2 - 20.5 = -18.5               <u>    342.25    </u>

        Total                                                              <u>   1057.5      </u>

Now, the mean of these value is given by;

        Mean, \bar X  =  \frac{\sum X}{n}

                         =  \frac{36+14+21+39+11+2}{6}

                         =  \frac{123}{6}  =  20.5

Standard deviation formula for discrete distribution is given by;

           Standard deviation, \sigma  =  \sqrt{\frac{\sum (X -\bar X)^{2} }{n-1} }

                                                 =  \sqrt{\frac{1057.5 }{6-1} } = 14.54

Now, the manager has six more samples taken:

33, 45, 34, 17, 1, and 29 errors, per 1,000 scans each

So, the modified table would be;

           X                            X - \bar X                            (X - \bar X)^{2}

          36                     36 - 23.5 = 12.5                   156.25

          14                      14 - 23.5 = -9.5                     90.25  

          21                       21 - 23.5 = -2.5                     6.25

          39                      39 - 23.5 = 15.5                   240.25

           11                        11 - 23.5 = -12.5                   156.25

           2                         2 - 23.5 = -21.5                   462.25    

          33                       33 - 23.5 = 9.5                     90.25

         45                        45 - 23.5 = 21.5                   462.25

         34                        34 - 23.5 = 10.5                   110.25

          17                         17 - 23.5 = -6.5                    42.25

           1                           1 - 23.5 = -22.5                   506.25

          29                        29 - 23.5 = 5.5               <u>     30.25      </u>

        Total                                                              <u>      2353      </u>

<u />

Now, the mean of these value is given by;

        Mean, \bar X  =  \frac{\sum X}{n}

                         =  \frac{36+14+21+39+11+2+33+45+34+17+1+29}{12}

                         =  \frac{282}{12}  =  23.5

Standard deviation formula for discrete distribution is given by;

           Standard deviation, \sigma  =  \sqrt{\frac{\sum (X -\bar X)^{2} }{n-1} }

                                                 =  \sqrt{\frac{2353 }{12-1} } = 14.62

7 0
3 years ago
Other questions:
  • a girl is snorkeling 1 meter below sea level and then she divides another 0.5 meters. How far below sea level is the girl?
    10·1 answer
  • ΔABC is similar to ΔAXY by a ratio of 3:2. If BC = 24, what is the length of XY?
    6·1 answer
  • Rectangle jklm is congruent to a 4 inch by 7 inch rectangle. How many different values are possible for the length of jm
    12·2 answers
  • A set of stairs is being built as shown. The length of each stair is 11 inches. What is the rise, r, for each stair? Round to th
    5·2 answers
  • The slope of MU if M (-1,1) and U(4,5)
    9·1 answer
  • What is 39/56 in simplest form
    6·2 answers
  • this summer you work at the grocery store where you can earn $7.50 per hour.how many hours,x,could you work to make at least $50
    7·1 answer
  • A) Unlimited movie rentals from a video store costing $19 a month
    8·1 answer
  • At the school store, pencils sell for $.12 each. The pencils come in boxes of 30. The school store buys each box for $2.00.
    13·2 answers
  • Find the area of the regular nonagon
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!