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
elixir [45]
3 years ago
9

A collection of 30 coins worth $5.50 consists of nickels, dimes, and quarters. There are twice as many dimes as nickels. How man

y quarters are there?
Mathematics
1 answer:
defon3 years ago
3 0
Three unknowns requires three equations to solve . . .

1) n + d + q = 30
2) d = 2n
3) (0.05)n + (0.10)d + (0.25)q = 5.50

* plug 2) into 1) and solve for q

n + 2n + q = 30

3n + q = 30

q = 30 - 3n

* now we have variables d and q expressed in terms of n, so we plug those equations into 3) and solve for n . . .


0.05n + 0.10(2n) + 0.25(30 - 3n) = 5.50

0.05n + 0.20n + 7.50 - 0.75n = 5.50

(0.05 + 0.20 - 0.75)n + 7.50 = 5.50

-0.50n + 7.50 = 5.50

-0.50n = 5.50 - 7.50

-0.50n = -2.00

n = -2.00/-0.50 = 4

d = 2n = 2(4) = 8

q = 30 - 3n = 30 - 3(4) = 30 - 12 = 18

The answer is . . .

n = 4 nickels
d = 8 dimes
q = 18 quarters

. . . for a total of (4 + 8 + 18) = 30 coins
. . . 8 dimes is twice 4 nickels
. . . $0.05(4) + $0.10(8) + $0.25(18) = $5.50
You might be interested in
Ok so I now fix it, can you help me?
11Alexandr11 [23.1K]

Answer:

1 80%

2 80%

3 80%

Step-by-step explanation:

7 0
3 years ago
Read 2 more answers
An airplane on auto pilot took 5 hours to travel 3,475 kilometers. What is the unit rate for kilometers per hour?
ExtremeBDS [4]
695 kilometers per hour
6 0
3 years ago
Use mental math to solve 4576 + 2842
allsm [11]
The answer is 7418.

Hope this helps
6 0
4 years ago
Read 2 more answers
Help please this is due today
dangina [55]

The experimental probability that in a group of 4 students, at least one of them has brown eyes is 95%.

<h3>What is Experimental Probability?</h3>

Experimental probability is a probability that is determined on the basis of a series of experiments. A random experiment is done and is repeated many times to determine their likelihood and each repetition is known as a trial. The experiment is conducted to find the chance of an event to occur or not to occur.

Here , Favorable Outcome = 19

          Total outcomes = 20

Probability = Favorable Outcome/ Total Outcome

                   = 19 / 20

                   = 95%

Thus, the experimental probability that in a group of 4 students, at least one of them has brown eyes is 95%.

Learn more about Experimental Probability from:

brainly.com/question/15729871

#SPJ1

5 0
2 years ago
The lawn is a circle with radius 3m.<br> Work out the area of the lawn.
Umnica [9.8K]

Answer:

28.27m

Step-by-step explanation:

the formula for area of a circle is

A= π x r^2

A = π x r^2 = π x 3^2 = 28.27433

5 0
2 years ago
Other questions:
  • Find the exact value of sin theta/12
    13·1 answer
  • Help me please i need help
    10·1 answer
  • To open a combination lock, you turn the dial to the right and stop at a number; then you turn it to the left and stop at a seco
    11·1 answer
  • PLEASE HELP ASAP! BRAINLIEST TO BEST/RIGHT ANSWER
    9·1 answer
  • At the time of writing, Kyla Lowry plays basketball with the NBA champions, the Toronto raptors. at one point he had played 805
    12·1 answer
  • Which statement is best supported by the information in the box plots?
    11·2 answers
  • Disneyland sells adult passes for $60 and youth passes for $30. In one day, 360 passes were sold for a total of $14,520. How man
    14·1 answer
  • 12x + 4x + 25y + 15y A. 2(8x + 10 B. 4(4x + 10) C. 5(3x + 5y D. 8(2x + 5y​
    7·2 answers
  • Jamal throws a bean bag into the air. This graph shows the height of the bean bag, h, in feet after t seconds.
    11·1 answer
  • Rewrite the equation below so that it does not have fractions.
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!