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
andriy [413]
3 years ago
10

No need of a answer anymore.

Mathematics
1 answer:
Rom4ik [11]3 years ago
5 0

Answer:

mean score of class B = 1778/25 = 71.12

Step-by-step explanation:

This was your question : Class A has 12 pupils and class B has 25 pupils. Both classes sit the same maths test. The mean score for class A is 80. The mean score for both classes is 74. What is the mean score (rounded to 2 DP) in the maths test for class B?

mean of class A = Σfx/Σf

mean of class A =  80

Σfx = 80 × 12 = 960

Mean score for both classes = 74

where

b = Σfx  of class B

960 + b/37 = 74

cross multiply

960 + b = 2738

b = 2738 - 960

b = 1778

mean score of class B = Σfx/Σf

Σfx = 1778

Σf = 25

Therefore,

1778/25 = 71.12

You might be interested in
I need help asap!!!! Please It’s an Algebra 2 question
Elza [17]

Answer:

8) Real; Rational

9) Real; Rational; Integer; Whole; Natural

10) Real; Rational

Step-by-step explanation:

Real numbers consists of the subsets:

Irrational Numbers:

Irrational numbers is the subset complementary to rational numbers. It includes numbers such as √(2) or π. These numbers do not repeat nor terminate.

Rational Numbers:

Rational numbers are all the others. They include the integers as well as the repeating and terminating decimals.

Integers:

Integers include the entire set of whole numbers and the negative numbers. This subset does not include decimals nor fractions. Thus, the integers are: ...-3, -2, -1, 0, 1, 2, 3... etc.

Whole Numbers:

Whole numbers is the set of natural numbers that <em>includes</em> 0. So, whole numbers are: 0, 1, 2, 3... and so on.

Natural Numbers:

Natural numbers or the counting numbers are all the positive, non-decimal numbers. These are 1, 2, 3... and so on. This set does not include 0.

8) 1.\overline{3}=1.3333...

The given number is not natural, whole, nor an integer because it is a decimal. It repeats, so it belongs to the rational numbers subset.

9) \sqrt4=2

The square root of 4 is simply 2. 2 is a natural number. Because of this, this means that 2 is also a whole number, integer, and a rational number.

10)-3/4=-0.75

The given number is a fraction and it does not reduce to a whole number, so it's not a natural number, whole number, nor an integer. It does terminate, so it belongs to the rational numbers subset.

7 0
3 years ago
Which statement explains why △ABC is congruent to △A′B′C′ ? You can map △ABC onto △A′B′C′ reflecting it across the line y = x an
Vikentia [17]
The <u>correct answer</u> is:

You can map ABC to A'B'C' by translating it 6 units left and reflecting it across the x-axis, which is a series of rigid motions.

Explanation:

In ABC, the coordinates are:
A(1, -3)
B(5, 3)
C(4, -1).

In A'B'C', the coordinates are:
A'(-5, 3)
B'(-1, -3)
C'(-2, 1)

Each point is mapped to its image:
A(1, -3)→A'(-5, 3)
B(5, 3)→B'(-1, -3)
C(4, -1)→C'(-2, 1)

Comparing the x-coordinates in the pre-image and image, we notice that the image has an x-coordinate that is 6 less than that of the pre-image:
1-6 = -5
5-6 = -1
4-6 = -2

This means that the figure must be translated 6 units left; that is the only way to have this change on the pre-image to form the image.

Comparing the y-coordinates of the pre-image with those of the image, we notice that they are negated:
-(-3) = 3
-(3) = -3
-(-1) = 1

This means the pre-image was reflected across the x-axis; this is the only way to negate the y-coordinate and not change the x-coordinate.

These are rigid motions because they do not change the shape or size, they simply move it and change its orientation.
3 0
3 years ago
Read 2 more answers
How do I find b,c and d? A is 108°
mylen [45]

Answer:

b = 72

c = 36

d = 144

Step-by-step explanation:

As every angle in the pentagon are equal (the lines inside every angle mean they are equal), angles on a straight line must add up to 180° ∴

A = 108°

108 + b = 180

180 - 108 = b

72 = b

As the top left angle of the triangle is also on a straight line with one of these angles, the value of this angle is also 72°.

All angles in a triangle must add up to 180° ∴

72 + 72 + c = 180

144 + c = 180

c = 180 - 144

c = 36

Angles on a straight line must add to 180° ∴

d + c = 180

d + 36 = 180

d = 180 - 36

d = 144

Hope this helps!

5 0
3 years ago
Read 2 more answers
PLEASE HELP MEEEEEEEEEEEEEEEEE
san4es73 [151]
The answer is -14jk....
8 0
3 years ago
There are some cubes in a bag
Charra [1.4K]

Answer:

Step-by-step explanation:

5 0
3 years ago
Other questions:
  • What is the approximate area of the shaded sector in the circle shown below? 
    14·2 answers
  • Word problem for the expression 8 × (-0.25)
    8·1 answer
  • Consider the polynomial 5x^2+8x-9. What is the degree of the polynomial?
    10·1 answer
  • The difference of twelve and twice a number b, divided by negative four. when b = -2
    12·1 answer
  • 5( - 2)<br><br><br> ............................................
    15·1 answer
  • SOMEBODY PLEASE HELP ME!!!!!!!​
    8·2 answers
  • If r(x) = 3x – 1 and s(x) = 2x + 1, which expression is equivalent to mc015-1.jpg?
    6·2 answers
  • What is 6.892 as a fraction
    11·2 answers
  • 17. A glider lands 20 miles east and 6 miles south from where it took off. The result of the trip can
    14·2 answers
  • A right triangle has side lengths of 6, 10, and x. find x if it is the hypotenuse
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!