A ladder 25m long reaches a window of building 20m above the ground. Then the distance of the foot of the ladder from the building is?  Choose the correct answer: A) 35m B) 45m C) 30m D) 15m E) 25m
let it forms a right angled triangle and follow c^2=a^2+b^2   then 25^2=20^2+b^2   b^2=625-400   b=15   ANSWER:15m
<result>D</result>
A ladder 25m long reaches a window of building 20m above the ground. Then the distance of the foot of the ladder from the building is?