What can be a counterexample for "the reciprocal of each natural number is an integer"?

Anne is twice as old as bill, and bill is 3 years older than christie. the sum of anne s and christie s ages equal 72. find their age difference.?

If i have a 24 in loaf of bread and i cut it into two pieces one 9 in how long was the other

Me asap on # : explain how factoring a trinomial, ax^2+ bx+ c, when a does not equal 1 different from factoring a trinomial when a = 1.