sample paper  maths of class 10 for fa1 cbse

 

The sum of the numerator and denominator of a fraction is 3 less than twice the denominator. If the numerator and denominator are decreased by 1, thge numerator becomes half the denominator, determine fraction

let numerator be x

denominator y

so fraction becomes x/y

according to question.....

x + y = 3-2y

x+y+2y=3

x+3y=3 (exuation 1)

case 2

x-1=y/2

y-1 y

x-1=y/2*1/y

y-1

x-1=2

y-1

x-1=2y-2

x-2y=-1 eq. 2

eq1-eq2

x+3y=3

-x+2y=1 (on subtracting signs change)

5y=4

y=5/4

replace the value of y in any equation you can find value of x too hence you can find fraction

x+y

asd

according to question.....

x + y = 3-2y

x+y+2y=3

x+3y=3 (exuation 1)

case 2

x-1=y/2

y-1 y

x-1=y/2*1/y

y-1

x-1=2

y-1

x-1=2y-2

x-2y=-1 eq. 2

eq1-eq2

x+3y=3

-x+2y=1 (on subtracting signs change)

5y=4

y=5/4

replace the value of y in any equation you can find value of x too hence you can find fraction