A is 10 miles west of B. C is 30 miles north of B. D is 20 miles east of C. What is the distance from A to D ?

Answer: Option E

Solution

Answer: Option E

Solution:

$$\begin{array}{rl}& \text{Required distance :}\\ & AD=\sqrt{{\left(AE\right)}^2+{\left(DE\right)}^2}\\ & =\sqrt{{\left(30\right)}^2+{\left(30\right)}^2}\\ & =\sqrt{900+900}\\ & =\sqrt{1800}\\ & =30\sqrt{2}\text{ miles}\end{array}$$