Math
posted by Sub .
Please let me know if is it true?
If exactly 15 seconds of speech are to be sampled at a rate of 44 100
samples per second and each sample is represented by 16 bits of data,
then the resulting file size will be more than 1.4 megabytes.

so each sample takes 2 bytes ( 8 bits = 1 byte)
number of bytes = 15(44100)(2) = 1323000
= 1.26 MB
I divided by 1024^2 instead of 1000^2
Since 2^10 = 1024 , a number close to 1000, very often we estimate by using multiples of 1000 instead of the true power of 2.
If I use just multiples of 1000, then it would have been
1.32 MB
Here is a page with the different units
http://www.techeez.com/windows_tips/bits_in_a_byte.htm