If knz≠0, what is the ratio of k to n? 1) The ratio of k to z is 2 to

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If knz≠0, what is the ratio of k to n?

1) The ratio of k to z is 2 to 3
2) The ratio of z to n is 4 to 5


In the original condition, there are 3 variables(k,z,n), which should match with the number of equations. So you need 3 equations. For 1) 1 equation, for 2) 1 equation, which is likely to make E the answer.
When 1) & 2), multiply 4 to k:z=2:3 and 3 to z:n=4:5, which makes k:z=8:12 and z:n=12:15 respectively. Then, k:z:n=8:12:15 is derived and k:n=8:15, which is unique and sufficient.
Therefore, the answer is C.