<PRE><B>Question 105755</B>
A microsecond is a millionth of a second. So in a millionth of a second this computer 
executes 36 instructions. So in a million microseconds (which is 1 second) the computer
does 36 million instructions. 
.
So what have we got at this point? We have found that each second the computer can execute
36 million instructions.  So in 60 seconds (which is 1 minute) the computer can execute
36 million instructions times 60 ... and this is (36*60) million instructions. Multiplying
this out you get 2160 million instructions each minute.  But you are asked to find the number
of instructions in 4 minutes ... so you multiply 2160 million times 4 to find out that in
4 minutes the computer does (2160*4) million or 8640 million instructions.
.
In long form this is 8,640,000,000 instructions in 4 minutes.
.
Hope this clarifies it for you ...
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