Leaving the job - questions about accrued annual leave pay out

My mother in law wants to retire and gave notice to her employer. Having had trouble with correct weekly pay at a few occasions, she is worried if she will be paid her accrued annual leave in the correct amount.

My mother in law works in a restaurant kitchen, 6 days per week with a gross hourly rate of $18. On average she works about 50 hours per week.

Where I have worked before the payslip usually shows how many hours annual leave I have accrued, calculated by a percentage of the hours I have worked. Her payslip however does not show any of that.

How are we able to calculate her annual leave pay out and see if the employer pays the correct amount?

Thank you in advance for any help you can provide!

http://www.dol.govt.nz/infozone/busi...oliday-pay.asp

I encashed my leaves with couple of previous employers and they calculated it correctly, it was bit simpler for me probably as I just calculated fortnightly salary (per day) and had just a little difference. You can still ask for the statement/salary slip from the employer which has list of deductions and calculations in it.