Question

जर $\frac{a}{b}=\frac{2}{3}$ तर पुढील राशीची किमत काढा: $\frac{7b-4a}{7b+4a}$

Answer 1

Solution :

$\frac{a}{b}=\frac{2}{3} ---(1)$

$\frac{7b-4a}{7b+4a}$

Divide numerator and

denominator by b , we get

= $\frac{7-4\frac{a}{b}}{7+4\frac{a}{b}}$

= $\frac{7-4\cdot\frac{2}{3}}{7+4\cdot\frac{2}{3}}$

= $\frac{7-\frac{8}{3}}{7+\frac{8}{3}}$

= [(21-8)/3]/[(21+8)/3]

= (21-8)/(21+8)

= 13/29

Or

Given a:b = 2/3

Let a = 2x , b = 3x

Now ,

(7b-4a)/(7b+4a)

= (7*3x - 4*2x)/(7*3x+4*2x)

= (21x-8x)/(21x+8x)

= 13x/29x

= 13/29

= 13 : 29

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