Questions

Sulphuric acid is called the King of Chemicals because it is used in the preparation of a very large number of other useful chemicals such as hydrochloric acid, nitric acid, dyes, drugs etc. In fact the annual production of shulpuric acid in a country is a measure of the economy of the country.

Mahanadi

As the frequency of sound is higher, women have shriller voices than men.

The shrillness or pitch of a sound is determined by its frequency. The higher the pitch shriller the voice. As the sounds produced by vocal cords of women are higher than men so women have shriller voices than men. Because their vocal cord is of smaller size. As their vocal cord is more stretched than men's.

Let the 5 digit number be represented by abcde.

Then the 6 digit number, 1abcde x 3 = abcde1 (another 6 digit number)

Now let Y = abcde

Then (100000 + Y) x 3 = (Y x 10) + 1

300000 + 3Y = 10Y + 1

7Y = 299999

Y = 299999 ÷ 7 = 42857