GIVEN: Two poles are 12 m apart and height of smaller pole is 7 m. Angle made by foot of smaller pole to top of taller pole is 45°. Speed of monkey = 26 km/h FORMULA USED: tanθ= Perpendicular / Base CALCULATION:
AB = PQ = 7 m BQ = AP = 12 m ∠TBQ = 45° Let TP = x Tan 45° = TQ/BQ ⇒ 1 = (x + 7)/12 ⇒ 12 = x + 7 ⇒ x = 5 AT2=TP2+AP2 ⇒AT2=52+122 ⇒ AT = 13 m Speed of monkey = 26 km/h = 26 × (5/18) = 65/9 m/s ∴ Required time taken = 13 ÷ (65/9) = 13 × (9/65) = 1.8 s