Q$.8.($a$)$ A manufacturing organization operates an incentive scheme on slab rates based on cost of

production as shown below :

Three workers X$,$ Y$,$ and Z take $25$ hours, $30$ hours and $15$ hours respectively to produce $10$ units of the

product and their respective wage rates are Rs$.\frac{6}{-},$ Rs$.\frac{6\mathrm{.}50}{?}-$ and Rs$.\frac{7}{?}-$ per hour. The material costs

Rs$.\frac{50}{?}-$ per unit and the overhead recovery rate is @ $500\%$ of cost of wages. The standard cost of

production per unit is determined as Rs$.175/-$ per unit.

What is the amount of incentive earned by each of these workers and what is the actual cost of

production per unit in each case?