Question
The speed of current is 5 km/h. What will be the
respective downstream speed and upstream speed of a boy rowing a boat, if half of the distance covered going downstream in a certain time is equal to the distance covered going upstream in the same time?Solution
Let the speed of boy in still water be X km/h. And the speed of current = 5 km/h Downstream speed = (X + 5) km/h Upstream speed = (X – 5) km/h Let time be ‘t’ hours. ⇒ [(X + 5) t]/2 = (X – 5) t ⇒ X + 5 = 2X – 10 ⇒ X = 15 km/h Downstream speed = 15 + 5 = 20 km/h Upstream speed = 15 – 5 = 10 km/h
A sum of Rs. 4,000 becomes Rs. 6,912 in 3 years at a certain rate of interest compounded annually. What is the rate of interest?
Which of the following may be the code for ‘lessons War’?
- In a 300-metre race, ‘Aman’ beats ‘Bhanu’ and ‘Charu’ by 30 metres and 60 metres, respectively. If ‘Bhanu’ and ‘Charu’ ran a 180 metre ...
In a certain code language, ‘201511920’ is related to 'TOAST' in the same way ‘321181851420’ is related to which of the following words?
...When entering text within a document, the Enter key normally pressed at the end of every
Which device connects a computer to a telephone line for internet access?
- The volume of a sphere is 288π cm³. What will be its surface area?
- The ratio between cost price, labelled price and the selling price of a product is 4:10:6. If a profit of Rs. 240 is gained on the sale, find out how much ...
- Priya bought a gadget at 40% discount on its listed price and later sold it by offering a 20% discount on the listed price. What was her profit percentage?
From the given answer figures, select the one in which the question figure is hidden / embedded(rotation is not allowed).
