20點 MATHS 暑期作業 ( 超難 ) ................唔 識 做 呀 ! ! ! THX~

1. Find the values of a and b such that in the expansion of (x+a)(x+b) , the
coefficient of the x term is a postitive number and the consant term is a
negative number.

2.Find two possible 3-digit denary numbers such that each of them can be
converted into a 8-digit binary number and a 2-digit hexadecimal number.

3.Find two possible binary numbers which are divisible by both 6 and 8 when they are converted into denary numbers.

4.How can we estimate the total number of residents of a builing? Write down the method.

5.Is it possible to find out the exact number of students in all the primary and
secondary schools in Hong Kong ? Explain it briefly.

6.Without using any measuring tools , estimate the height of the building you
are living , and write down the method used.



唔該答得清楚D呀...........


THX..................