math
posted by anonymous on .
A number X is 3 times greater than the number Y, and Y is 3 times greater than Z. If the sum of Y and Z is equal to 50, what is the value of X?
Please show working out, thanks.

Just translate ...
x = 3y , and y = 3z
y+z = 50
3z + z = 50
4z = 50
z = 25/2 or 12.5
then y = 3z = 3(12.5) = 37.5
x = 3y = 3(37.5) = 112.5