well this is easyyy:) you just need to multiply 4 and 2/7 by 1/2
buttt before we set up our question lets get 4 and 2/7 as an improper fraction 
 2
4 ----
 7
we do that by multipying the 4 and 7 and then adding 2 soo lets do that 
4 x 7 = 28 
28 + 2 = 30 
look we have our numerator!! (the top number)
and we dont have to do anything to the numerator just keep it the same as 7 :) lets look at our new improper fraction
 30 
------
 7
see now we can set up our problem:)
 30 1
------ x -----
 7 2
now all we do is multiply across:)
 30 1 = 30 x 1 = 30 
------ x -----
 7 2 = 7 x 2 = 14 
here is our new fraction
 
 30
------
 14
wait lets simplify it by dividing each number by 2 
 30 ÷ 2 = 15 
------
 14 ÷ 2 = 7 
ahh this is better here is our simpified fraction
 
  15 
-------
 7
or as a decimal it is 2.142857143 
either one is the correct answer:)
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