Q26 of 186 Page 3

10 students of class X took part in mathematics quiz. If the number of girls is 4 more than the number of boys, find the number of boys and girls who took part in the quiz.

Let the number of boys = x

and the number of girls = y


Now, table for x + y – 10 = 0



Now, table for x – y + 4 = 0



On plotting points on a graph paper and join them to get a straight line representing x + y – 10 = 0.


Similarly, on plotting the points on the same graph paper and join them to get a straight line representing x – y + 4 = 0.



∴ x = 3, y = 7 is the solution of the pair of linear equations.


Hence, the required number of boys is 3 and girls is 7.


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