Class 8 Linear Equation (in one variable)
Linear equation: The equation in which one variable present and highest degree is 1 is called linear equation in one variable.
Equation: An equation is a statement of equality of two algebraic expressions involving one or more unknown quantities, called variables.
Rules for solving a linear equation:
i) we can at the same number on both sides of the equation
ii) we can subtract the same number from both sides of the equation
iii) we can multiply both sides of the equation by the same non zero number
iv) we can divide both sides of the equation by the same non zero number.
1) two numbers are in the ratio 5 : 4. Is the sum of the numbers is 207,find the numbers. 
2) 3/4 of are number is 10 less than the original. Find the number.
3) Five-sixth of a number is 20 more than three-fourths of the number. Find the number.
4) Thirty is divided into two parts such that 6 times of the first part added to 2 4 times the second part makes 140. Find the numbers.
7) If 20 be added to five times a number, the result is is 10 less than 6 times the number. Find the number.
8) Two numbers are such that the ratio between them is 4 : 5 . If each is increased by 20, the ratio between the new numbers so formed is 6 : 7 . Find the original numbers.
9) the sum of three consecutive numbers even numbers is equals to 306. Find the numbers.
10) find three consecutive odd numbers whose sum is 339.
11) The sum of the digits of a two digit number is 15. The new number which is formed by reversing the digits is 9 lesser than the original number. find the original number.
12) the digit in the tens place of a two digit number is 4 times that in the units place. if the digits are reversed, the new number will be 54 less than the original number. Find the original number.
13) The denominator of a rational number is greater than its numerator by 18. If the numerator is increased by 23 and the denominator is decreased by 15, the new number becomes 3. Find the original number.
