From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : A part of monthly expenses of a family is constant and the remaining varies with the price of wheat. When the cost of wheat is ? 500 a Quintal the total monthly expenses are ? 1500 and when it is ? 600 a quintal, the total monthly expenses are ? 1700. Find the monthly expenses whefl' the cost of wheat is ? 900 a quintal.

Form the pair of linear equations in the following problems and find their solutions (if they exist) by any algebraic method :- A part of monthly expenses of a family is constant and the remaining varies with the price of wheat. When the cost of wheat is Rs 250 a quintal, the total monthly expenses of the family are Rs 1000 and when it is Rs 240 a quintal, the total monthly expenses are Rs 980. Find the total monthly expenses of the family when the cost of wheat is Rs 350 a quintal

From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : There are rs 2 and rs 5 coins in a purse. If there are 60 coins of value rs 195, find the number of coins of each kind.

From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : A certain number of two digits is three times the sum of its digits and if 45 be added to i,t the digits will be reversed. Find the number.

From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : Find the fraction which becomes equal to 1/3 when the numerator is increased by 1 and equal to 1/4 when denominator is increased by 1.

From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : I am three times as old as my son. Five year later, I shall be two and a half times as old as my son. How old am I and how old is my son ?

Form the pair of linear equations in the following problems, and find their solutions (if they exist) by the elimination method : Five years ago, Nuri was thrice as old as Sonu. Ten years later, Nuri will be twice as old as Sonu. How old are Nuri and Sonu ?

Form the pair of linear equations in the following problems and find their solution by substitution method : A horse and 2 cows together cost ? 680. If a horse costs ? 80 more than a cow, find the cost of each.

From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : If we add 3 to the numerator and subtract 2 from the denominator, a fraction becomes 2. It also becomes 1/2 if we add 1 to the denominator. Find the fraction.

From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : Seven times a given two digit number is equal to four times the number obtained by interchanging the digits and the difference of digits is 3. Find the number

From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : A man wanted to exchange Rs 1000 in 2 types of notes of Rs 5 and Rs 10 denominations. If he has 180 notes in all, find the number of notes of each kind.