If the mean of numbers 28, x, 42, 78 and 104 is 90, then what is the mean of 128, 255, 511, 1023 and x?	Choose the correct choice:  A) 395  B) 275  C) 355  D) 423  E) 365
The mean of numbers 28, x, 42, 78 and 104 is 62: 28+x+42+78+104=90*5 --&gt; x=198;   So, the mean of 128, 255, 511, 1023 and x is  (128+255+511+1023+198)/5= 
<gadget id="calculator"> (128+255+511+1023+198)/5</gadget>
<output>423</output>
423.   Answer:423.
<result>D</result>
If the mean of numbers 28, x, 42, 78 and 104 is 90, then what is the mean of 128, 255, 511, 1023 and x?