This is what I tried: combined c23 into 30microF
CT= 1/[1/30+1/30+1/30] = 10.10
XC=1/2(pie)fc f=1000 c=10.10
0.00001576 was my answer.

 

You have a rounding error in the total effective capacitance calculation that is large enough to affect the answer.
Hint: Without using a calculator, add the contents of the brackets first and look for a common denominator.
Second hint: In the formula, XC is Ohms, f is Hz and C is Farads.
Regards,
Keith