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Moles of Crystallisation from a Titration Problem

This is probably really straightforward but can't spot what I'm doing wrong.

Q: Calculate the Mr of CoCl₂.xH₂O and the value of x. 1.80g of hydrated cobalt(II) chloride was dissolved in water and made up to 200cm³. 25cm³ of this solution required 35.17cm³ of 0.0500 moldm^-3 silver nitrate solution for complete reaction.
Ag⁺ + Cl^- -> AgCl

My thought process was..
Moles Ag⁺ = 0.03517 * 0.05 = 1.7585 * 10^-3 mol
Moles Cl^- in 200cm³ = 0.0017575 * 200/25 = 0.014068 mol
Mr CoCl₂ = 129.8
Mass of CoCl₂ = 129.9 * 0.014068 = 1.827g
Mass xH₂0 = 1.80 - 1.827 = ERROR

Would be really grateful for someone to point out my mistake(s) or guide me through the best method for working out these types of problems.

Many thanks,
Dan

EDIT: I've realised my mistake. Hopefully x=7 is correct.