BECE Mathematics 2016 Paper

Concept:Translate the word problem into a simple algebraic equation and solve for the unknown number.Explanation:Let the required number be $x$.When the number is doubled, it becomes $2x$.This result is decreased by $9$, so we subtract $9$: $2x - 9$.The answer is given as $19$, so the equation is:$$2x - 9 = 19$$Add $9$ to both sides to isolate the term with $x$:$$2x = 19 + 9$$$$2x = 28$$Divide both sides by $2$:$$\frac{2x}{2} = \frac{28}{2}$$$$x = 14$$Answer:The number is $14$, which is option C.