Exams

The mean of 21 observations (all different) is 40. If each observation greater than the median is increased by 21, then the mean of observations will become:

Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.

Crude mineral oil comes out of the earth as a thick brown or black liquid with a strong smell. It is a complex mixture of many different substances, each with its own individual qualities. Most of them are combinations of hydrogen and carbon in varying proportions. Such hydrocarbons are also found in other forms such as bitumen, asphalt and natural gas. Mineral oil originates from the carcasses of tiny animals and from plants that live in the sea. Over million of years, these dead creatures form large deposits under sea­bed and ocean currents cover them with a blanket of sand and silt. As this material hardens, it becomes sedimentary rock and effectively shuts out the oxygen, thus preventing the complete decomposition of the marine deposits underneath. The layers of sedimentary rocks become thicker, and heavier. Their pressure produces heat, which transforms the tiny carcasses into crude oil in a process that is still going on today.

What is crude mineral oil?

A does 80% of a work in 20 days. He then calls in B and they together finish the remaining work in 4 days. How long B alone would take to do the whole work?

If angles of measure (5y + 62°) and (22° + y) are supplementary , then value of y is

What is the measure of central angle of the arc whose length is 11 cm and radius of the circle is 14 cm?

A Navy captain going away from a lighthouse at the speed of 4[(√3) – 1] m/s. He observes that it takes him 1 minute to change the angle of elevation of the top of the lighthouse from 60 to 45 deg. What is the height (in metres) of the lighthouse?

Choose the  word  which  is  nearly opposite in meaning to the given word ‘PREDILECTION’

Deficiency of fluoride leads to Which one of the following health problems?