is 1 is subtracted from numerator and denominator of a fraction the value is obtained 1 upon 2 if 1 is added to its numerator and denominator the value is 2 upon 3 find the fraction

Find the volume of the described solid.the solid lies between planes perpendicular to the x-axis at x = 0 and x=7. the cross sectionsperpendicular to the x-axis between these planes are squares whose bases run from the parabolay=-31x to the parabola y = 30/x.a) 441b) 147c) 864d) 882