Let current age be x, next we construct the inequalities for the age: <span>Four-fifths of my current age is greater than three-quarters of my age one year from now. </span>thus when we add 1 year to 3/4 of our current age and set the inequality 4x/5>3x/4+1......i
<span>Four-fifths of my current age is also greater than five-sixths of my age one year ago. Thus when we subtract 1 from 5x/6 and set the inequality we get 4x/5>5x/6-1.......ii solving the inequalities we obtain: </span>4x/5>3x/4+1 x/20>1 hence multiplying both sides by 20 we obtain: x>20
also
4x/5>5x/6-1 4x/5-5x/5>-1 -x/30>-1 multiplying both sides by 30 we get: -x>-30 thus x<30 therefore the possible values of my age will lie in the interval: 20<x<30 Thus our age is in the interval (20,30)
