What should come in place of question mark (?) in the following number series.
12, 6.5, 7.5, 12.75, 27.5, 71.25, ?
16, 24, 36, 54, 81, 121.5, ?
12, 12, 18, 45, 180, 1170, ?
22, 23, 27, 36, 52, 77, ?
16, 14, 24, 66, 256, 1270, ?
Study the following table carefully to answer the questions that follow :
No of boys and girls in five streams of a college over the years.

What is the total number of boys, for all the streams together, in the year 2004 ?
The number of boys in Arts stream in the year 2004 is approximately what per cent of the total number of boys for all the years together in Arts stream ?
What is the ratio of the total number of boys to the total number of girls, from all the streams together, for the year 2007 ?
What is the ratio of the total number of boys to the total number of girls, in the Management stream for all the years together ?
What is the average number of Girls from Commerce stream for the given years ?