A positive fraction is greater than its reciprocal by 72/77. What is the fraction?
Let the fraction be $$x$$
According to ques,
=> $$x-\frac{1}{x}=\frac{72}{77}$$
=> $$\frac{x^2-1}{x}=\frac{72}{77}$$
=> $$77x^2-77=72x$$
=> $$77x^2-72x-77=0$$
=> $$77x^2-121x+49x-77=0$$
=> $$11x(7x-11)+7(7x-11)=0$$
=> $$(7x-11)(11x+7)=0$$
=> $$x=\frac{11}{7},\frac{-7}{11}$$
$$\because x$$ is positive, => $$x=\frac{11}{7}$$
=> Ans - (B)
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