For each month of a given year except December, a worker earned the same monthly salary and donated one-tenth of that salary to charity. In December, the worker earned N times his usual monthly salary and donated one-fifth of his earnings to charity. If the worker's charitable contributions totaled one-nineth of his earnings for the entire year, what is the value of N?  Choose one
A) 8/5 B) 5/2 C) 3 D) 11/3 E) 22
Let monthly salary for each of the 11 months except December was x, then   11x*1/10 + Nx*1/5 = 1/9(11x + Nx);   11/10 + N/5 = 1/9(11 + N)=&gt;   11+2N/10 = 11+N/9=&gt;66+12N=110+10N =&gt;2N=44   N = 22   Answer: 22
<result>E</result>
For each month of a given year except December, a worker earned the same monthly salary and donated one-tenth of that salary to charity. In December, the worker earned N times his usual monthly salary and donated one-fifth of his earnings to charity. If the worker's charitable contributions totaled one-nineth of his earnings for the entire year, what is the value of N?