Skip to main content

Aptitude Day 251

Boats and Streams

Rules to be followed:

  • The direction along the stream in water is called downstream and the direction against the stream is called upstream.
  • If the speed of a boat in still water is u km/hr and the speed of the stream is v km/hr, then:
                    Speed of the downstream = u+v km/hr.
                    Speed of the upstream = u-v km/hr.
  • If the speed of the downstream is a km/hr and the speed of the upstream is b km/hr, then:
                       Speed in still water = 1/2(a+b) km/hr.
                       Rate of the stream = 1/2(a-b) km/hr.

A Problem on Boats and Streams:

1. In 1 hour, a boat goes 9km along the stream and 3km against the stream. The speed of the boat in still water (in km/hr) is:
Solution:
                  Speed in still water = 1/2[9+3] 
                                                 = 6 km/hr.



Comments

Post a Comment

Popular posts from this blog

Vocabulary Day 60

Incur Thesaurus: Verb :  arouse            acquire, earn, gain, include, get, obtain...  Antonyms :  lose, exclude ...  Example sentences:         ·        He is incurred in that game. ·        She incurs a great knowlegde in science.        
Post a Comment
Read more

Vocabulary Day 82

Flutter Thesaurus: Verb: wave rapidly            drift, agitate, dance, flicker, fluctuate, hover, oscillate, quiver, shake, vibrate...                                           Antonyms:  stay, remain, stay . ..  Example sentences:         ·        His heart flutters when he sees his crush.  ·       That incident causes a  flutter between them. 
Post a Comment
Read more

Aptitude Day 5

Answers of Day 4 :   1. 9                                   2. 5                                   3. 9                                   4. 8 To find the unit digit in the product. This is similar to the last model where we will find the unit digit of the sum. Example: 432*459*28*48=? Solution:  2*9=18 , 8*8=64, 4*8= 32. The unit digit of the total product is 2.  Problems to solve Find the unit digit of the product in the following 1. 404*397*810*21 =? 2. 24*42*36*78 =? 3. 81*82*89 =? 4. 72*36*98*47 =? See you tomorrow friends... Check out the answers over here  Aptitude Day 6
Post a Comment
Read more