Each of the numbers w,x,y,and z is equal to either 0 or 1.What is the value of w+x+y+z?
1)w/2+x/4+y/8+z/16=11/16
2)w/3+x/9+y/27+z/81=31/81
OA is D..this is a question from GPREP...
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Number Game
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zagcollins
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IMO is D
Since w,x,y,z can have either 0 or 1
from (i)
Keep the denominator equal to 16
8(1) + 4(0) + 2(1) + 1(1) = 11
11 Could be acheived only when wxyz = {1011} ==> 8+2+1
So w+x+y+z=3
Similarly with (ii)
Keep the denominator equal to 81
27(1) + 9(0) + 3(1) + 1(1) = 31
So Answer is D
Whats OA???
Since w,x,y,z can have either 0 or 1
from (i)
Keep the denominator equal to 16
8(1) + 4(0) + 2(1) + 1(1) = 11
11 Could be acheived only when wxyz = {1011} ==> 8+2+1
So w+x+y+z=3
Similarly with (ii)
Keep the denominator equal to 81
27(1) + 9(0) + 3(1) + 1(1) = 31
So Answer is D
Whats OA???
