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Commercial Mathematics of Class 8

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Question of Exercise 5

Commercial Mathematics of Class 8

Question
The cost of manufacturing a commodity increased by 20%. Atraderwho did not revise the selling price noted that there was a drop of Rs. 20 in his profit. What is the orginai cost price ?

Frequently Asked Questions

Write the coefficients of x^2 in each of the following

(i) 2 + x^2 + x

(ii) 2 - x^2 + x^3

(iii)  pi/2x^2 + x

(iv) √(2)x - 1

Solution:

Explanation:

A coefficient is a number or quantity that is associated with a variable. It's commonly an integer multiplied by the variable immediately adjacent to it.

(i) 2+x 2 +x

The x 2 coefficient is 1.

(ii) 2-x 2 +x 3

The x 2 coefficient is -1.

(iii) (π/2)x 2 +x

The x 2 coefficient is π /2.

(iv)√2x-1

In the provided formulation, there is no x2 term. It can be rewritten as 0x 2 +√ 2x - 1

The coefficient of x 2 equals 0 because x 2 does not exist.

Final Answer:

(i) 2+x 2 +x , the coefficient of  x 2 is 1.

(ii) 2-x 2 +x 3 , the coefficient of   x 2 is -1.

(iii) (π/2)x 2 +x, here the coefficient of   x 2 is  π/2.

(iv) √2x-1, the coefficient of   x 2 is  0.

Which of the following is are correct

A:6 ÷ 3 =2

B:3 ÷ 6 =1/2

C:6 ÷ 3 ≠ 3 ÷ 6

D: None of the above

Solution:

Explanation

pic21

How many faces and edges does a triangular prism have

Solution:

Explanation:

  • The triangular prism's sides and bases are either congruent or oblique.
  • The prism's edges connect to the appropriate sides.
  • The two bases of this prism are equilateral triangles, and their edges are parallel to one another.
  • To grasp the structure, look at the diagram below.

triangular prism

  • It contains 9 edges, 5 faces, and 6 vertices in total (which are joined by the rectangular faces).
  • It features three rectangular sides and two triangular bases.
  • The triangular prism is considered to be semiregular if the triangular bases are equilateral and the other faces are squares rather than rectangles.

Final Answer:

5 faces and 9 edges.

Find the cube root of 125

Solution:

Explanation:

  • A number's cube root is a number that, when multiplied three times, returns the original number 125.
  • The cube root of 125 is represented as ∛125 using the 3rd root sign.
  • Let P be an integer such that its cube is 125, P 3 = 125 or .
  • Assume that P = 1,2,3... and that its cube equals 125.

1 x 1 x 1 = 1

2 x 2 x 2 = 8

3 x 3 x 3 = 27

4 x 4 x 4 = 64

5 x 5 x 5 = 125

  • As a result, ∛125 = ∛5x5x5=5 .

Final Answer:

Hence, the cube root of 125 is 5 .

Find the square root of 5

pic6

Solution:

From the question, we have to find the square of pic6 .

So,

pic7

Final Answer:

Square root is pic8 .

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