## Chapter 6 - Framing of Formulae Exercise Ex. 6.1

Question 1
The simple interest on a sum of money is the product of the sum of money, the number of years and the rate percentage. Write the formula to find the simple interest on Rs A for T years at R% per annum.
Solution 1
Question 2
Solution 2
Question 3
The fahrenheit temperature, F is 32 more than nine -fifths of the centigrade temperature C. Express this relation by a formula.
Solution 3
Question 4
The arithmetic mean M of the five numbers a, b, c, d, e is equal to their sum divided by the number of quantities. Express it as a formula.
Solution 4
Question 5
Make a formula for the statement :"The reciprocal of focal length f is equal to the sum of reciprocals of the object distance u and the image distance v."
Solution 5
Question 6
Make a formula for the statement:"The number of diagonals, d, that can be drawn from one vertex of an n sided polygon to all the other vertices is equal to the number of sides of the polygon less 3"
Solution 6
Question 7
Solution 7
Question 8
A man bought 25a articles at 30p paisa each and sold them at 20q paisa each. Find his profit in rupees.
Solution 8
Question 9
How many minutes are there in x hours, y minutes and z seconds.
Solution 9
Question 10
Apple cost x rupees per dozen and mangoes cost y rupees per score. Write a formula to find the total cost C in rupees of 20 apples and 30 mangoes.
Solution 10

## Chapter 6 - Changing the subject of a formula Exercise Ex. 6.2

Question 1
Given: mx + ny = p and y = ax + b. Find x in terms of m, n, p, a and b.
Solution 1
Question 2
If A =  pr2 and C = 2pr, then express r in terms of A and C.
Solution 2
Question 3
If V = pr2h and S = 2pr2 + 2prh, then express V in terms of S, p and r.
Solution 3
Question 4
If 3ax + 2b2 = 3bx + 2a2, then express x in terms of a and b. Also, express the result in the simplest form.
Solution 4
Question 5

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Question 6
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Question 7
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Question 8
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Question 9
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Question 10
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Question 11
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Question 12
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Question 13
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Question 14
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Question 15
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Question 16
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Question 17
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Question 18
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Question 19
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Question 20
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## Chapter 6 - Changing the subject of a formula Exercise Ex. 6.3

Question 1
The pressure P and volume V of a gas are connected by the formula PV = C; where C is a constant.

Solution 1
Question 2
The total energy E possess by a body of Mass 'm', moving with a velocity 'v' at a height 'h' is given by:
Make 'm' the subject of formula.
Solution 2
Question 3
The total energy E possess by a body of Mass 'm', moving with a velocity 'v' at a height 'h' is given by:
Find m, if v = 2, g = 10, h = 5 and E = 104.
Solution 3
Question 4

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Question 5
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Question 6
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Question 7
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Question 8
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Question 9
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Question 10
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Question 11
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Question 12
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Question 13
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Question 14
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Question 15
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Question 16
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Question 17
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Question 18
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Question 19
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Question 20
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Question 21
Solution 21