4 x y z
x = 2 y but x is <5 so y = 0, 1, or 2
4 + 2y + y + z = 12
so
x + 3y + z = 8
if y = 0, then twice y is also 0 nope
if y = 1, then twice y = 2, nope 421 three digits
if y = 2 , then 4 4 2 z
then if z = 2, the sum is 12
how about 4422 ???
A number rounds off to 4000. The digit in the hundreds place is twice the digit in tens place. The sum of the digit is 12. The numbers uses only two different digits. Find the number.
2 answers
if the number is 3xxx with x>5, then the minimum sum is 3633=15 so, that will not work
If the number is 4xxx, then there must be 2 4's and 2 2's. That leaves only 4422 as a possibility.
If the number is 4xxx, then there must be 2 4's and 2 2's. That leaves only 4422 as a possibility.