POPULATION

City A's population is 68000, decreasing at a rate of 80 people per year. City B having population 42000 is increasing at a rate of 120 people per year. In how many years both the cities will have same population?

 Answer: 

 130 years.

Comments

Post a Comment

Popular posts from this blog

Milk and Water

A milkmaid adds 4 litres of water to 2 litres of milk before distribution. By mistake she added 2 litres water to 4 litres of milk. How much more water has she to add to rectify her mistake? Answer: Six litres. Water should be double than the milk content. the present content is 4 litres. Hence, the total water should be 8. it has 2 litres already. So, another 6 litres are to be added.
Read more

Tricky equation

Suppose a=b. With this equation, I will prove that a + b = b in four steps. Find out where (in which step) I went wrong? Step one: if a=b, then a²=ab. Step two: Deduct b² from both: (a² - b²) = (ab - b²). Step three: (a + b) (a - b) = b (a - b). Step four: Deduct (a-b) from both: a + b= b. How is this possible? In which step lies the mistake? Answer: The mistake is in step three A-B=0. You cannot conclude that 4 = 2 just because 4 x 0 = 2 x 0.
Read more