WAEC Mathematics 2020 Paper

Concept:The amount obtained after simple interest equals the original principal plus the interest earned on it.Explanation:Let the principal be $x$.It was saved at 2% simple interest for 5 years.So, $\text{S.I.} = \frac{x \times 2 \times 5}{100} = 0.1x$.The amount realized is given as N550,000.00.Amount $=$ Principal $+$ Simple Interest.Therefore, $x + 0.1x = 550{,}000$.That is, $1.1x = 550{,}000$.Divide both sides by $1.1$: $x = \frac{550{,}000}{1.1} = 500{,}000$.Hence, the principal is N500,000.00.Answer:D. N500,000.00