Question

if x:y=8:9,find the ratio(7x-4y) : (3x+2y)

Answer 1

Given that x : y = 8 : 9 ----- : ( 1 )




Therefore ,

= > ( 7x - 4y ) : ( 3x + 2y )



Divide by y on numerator and denominator both ,


$= > \frac{ \frac{7x - 4y}{y} }{ \frac{3x + 2y}{y} } \\ \\ \\ \\ = > \frac{ \frac{7x}{y} - \frac{4y}{y} }{ \frac{3x}{y} + \frac{2y}{y} }$




Putting value of x : y from ( 1 ) ,


$= > \frac{ \frac{7 \times 8}{9} - 4(1)}{ \frac{3 \times 8}{9} + 2(1) } \\ \\ \\ \\ = > \frac{ \frac{56 - 36}{9}}{ \frac{24 + 18}{9} } \\ \\ \\ \\ = > \frac{20}{42} \\ \\ \\ \\ = > \frac{10}{21}$





Hence, value of ( 7x - 4y ) : ( 3x + 2y ) = 10 : 21