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
d1i1m1o1n [39]
3 years ago
5

The mean of 7 numbers is 15. When an 8th number is added the mean decreases to 12. What is the 8th number?

Mathematics
1 answer:
ale4655 [162]3 years ago
3 0

Answer:

The 8th number is -9

Step-by-step explanation:

With an average, the sum of the seven numbers divided by 7 is 15.

In order to add an 8th number, we set up

\frac{7*15+x}{8}=12\\105 + x = 96\\x = -9\\\\\frac{105-9}{8}=\frac{96}{8}=12

You might be interested in
11 pounds 13 ounces = ounces
lawyer [7]
1 pound = 16 ounces so let's go ahead and convert 11 pounds to ounces by multiplying by 16. 11×16=176 and then add 13 to that 176+13=189

so 12 pounds and 13 ounces= 189 ounces


6 0
3 years ago
5 students want ice cream, 7 want a movie, 10 want a custom, and the rest are undecided. If 20% want ice cream how many students
Nataly [62]
There are 25 in the class
8 0
3 years ago
You can buy 5 cans for green beans at the village market for 3.70. You can buy 10 of the same cans of beans at sams club for 4.1
il63 [147K]

the rate for 5 cans for $3.70 is 0.74

the rate for 10 cans for $4.10 is 0.41

so the better buy is 10 cans for $4.10 at sams

4 0
3 years ago
Fatima wants you to show her some numbers other than pie that are real but not rational what would you show her?
EastWind [94]
REAL BUT NOT RATIONAL :
square root of 2
the golden ratio : 1.618033.....non terminating
square root of 99
8 0
3 years ago
What is m∠PTR? a. 12 b. 40 c. 50 d. 140 HELP!!!
kramer

Answer:

m<PTR = 140°

Step-by-step explanation:

First, find the value of x. To find the value of x, derive an equation which you'd use in solving for x.

m<PTQ = (x + 28)°

m<RTS = (2x + 16)°

m<PTQ = m<RTS (vertical opposite angles are congruent)

Therefore:

x + 28 = 2x + 16

Solve for x. Combine like terms

28 - 16 = 2x - x

12 = x

x = 12

Find m<PTQ

m<PTQ = (x + 28)

plug in the value of x

m<PTQ = 12 + 28 = 40°

m<PTR + m<PTQ = 180° (supplementary angles)

m<PTR + 40° = 180° (substitution)

m<PTR = 180 - 40 (subtracting 40 from each side)

m<PTR = 140°

3 0
3 years ago
Other questions:
  • 9x – 5 &lt; –41 or 3x + 13 &gt; 7
    7·2 answers
  • I'm a bit confused. Can someone help?
    8·1 answer
  • Sean used candle molds, as shown, to make candles that were perfect cylinders and spheres:
    9·1 answer
  • Does a charge battery have potential energy
    15·1 answer
  • What is the solution to the system of equations <br> 1/4x+1 1/2y=5/8 <br> 3/4x-1 1/2y=3 3/8
    8·1 answer
  • Two numbers have a sum of 93. If one number is p, express the other number in terms of p.
    6·1 answer
  • What is the definition of a real number?
    13·2 answers
  • Do I multiply 60% of 68
    9·2 answers
  • 9.75t + 9 = 18.5t + 16
    11·2 answers
  • For what values of x is the expression below defined?<br> √x+4÷√1-x
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!