I have tried this question a few different ways and have arrived at -718167 each

Question

I have tried this question a few different ways and have arrived at -718167 each time, which is incorrect. Can someone please walk me through the steps to solve this problem?
A small 12.5g plastic ball is tied to a very light 29.7cm string that is attached to the vertical wall of a room. A uniform horizontal electric field exists in this room. When the ball has been given an excess charge or -1.4 microCoulombs, you observe that it remains suspended, with the string making an angle of 17.4 degrees with the wall. Find the madnitude of the electric field in the room.

Explanation / Answer

so sum forces in the y

T cos theta - mg = 0

T = mg/cos theta

sum in the x

q E - T sin theta = 0

q E - m g tan theta = 0

E = m g tan theta/q = 12.5E-3*9.81*tan(17.4 degrees)/1.4E-6= 27449 N/C

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