Question 857977: If v,w,x,y,z are non negative integers,each less than 11,then how many distinct combinations of v,w,x,y,z satisfy v(11^4)+w(11^3)+x(11^2)+y(11)+z=151001
Answer by Edwin McCravy(20054) (Show Source):
You can put this solution on YOUR website!
Dividing 151001 by 11^4 give quotient 10 and remainder 4591
So
151001 = 10*11^4 + 4591
Dividing 4591 by 11^3 gives quotient 3 and remainder 598
So
151001 = 10*11^4 + 3*11^3 + 598
Dividing 598 by 11^2 gives quotient 4 and remainder 114
So
151001 = 10*11^4 + 3*11^3 + 4*11^2 + 114
Dividing 114 by 11 gives quotient 10 and remainder 4
So
151001 = 10*11^4 + 3*11^3 + 4*11^2 + 10*11 + 4
So v=10, w=3, x=4, y=10, z=4
is ONE solution. But is that the only one? We will
show that it indeed is the only solution:
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So we show that that is the ONLY solution.
v cannot be larger than 10.
Suppose that v could be less than 10, then the largest
v(11^4)+w(11^3)+x(11^2)+y(11)+z
could possibly be would be when v=9, w=10, x=10, y=10, z=10
9(11^4)+10(11^3)+10(11^2)+10(11)+10 = 146409
But that is less than 151001. So v can only be 10.
So we know that:
10(11^4)+w(11^3)+x(11^2)+y(11)+z=151001
146410+w(11^3)+x(11^2)+y(11)+z=151001
w(11^3)+x(11^2)+y(11)+z=4591
If w were more than 3, the smallest
w(11^3)+x(11^2)+y(11)+z
could be is when w=4,x=0,y=0,z=0
4(11^3)+0(11^2)+0(11)+0 = 5324
But that is larger than 4591, so w is not greater than 4.
On the other hand,
If w were less than 3, the largest
w(11^3)+x(11^2)+y(11)+z
could be is when w=2,x=10,y=10,z=10
2(11^3)+10(11^2)+10(11)+10 = 3992
But that is smaller than 4591, so w is not less than 3 either.
Therefore w = 3 is the only possibility, and
3(11^3)+x(11^2)+y(11)+z = 4591
x(11^2)+y(11)+z = 598
If x were more than 4, the smallest
x(11^2)+y(11)+z
could be is when x=5,y=0,z=0
5(11^2)+0(11)+0 = 605
But that is larger than 598, so w is not greater than 4.
On the other hand,
If x were less than 4, the largest
x(11^2)+y(11)+z
could be is when x=3,y=10,z=10
3(11^2)+10(11)+10 = 483
But that is smaller than 598, so x is not less than 4 either.
Therefore x = 4 is the only possibility, and
4(11^2)+y(11)+z = 598
y(11)+z = 114
Y cannot be more than 10.
If y were less than 10, the largest
y(11)+z
could be is when y=9,z=10
9(11)+10 = 109
But that is smaller than 114, so x = 10.
So we have proved that v=10, w=3, x=4, y=10, z=4
is the only solution.
Edwin
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