june 2011 q3

There are 6 days x 4 weeks = 24 days in a month.
The actual number of meals are 1560, and so there are 1560 / 24 = 65 orders per day.
The budget was prepared assuming 50 orders a day and so we need to flex it for an extra 15 a day.
The question says in note 5, that for every 5 extra orders the staff work 0.5 hours of overtime. So it means that for 15 extra a day they will work 1.5 extra hours.
For this they are paid $12 per hour, so 1.5 x 12 = $18 extra a day.
There are 24 days, and 8 staff, which means an extra 8 x 24 x 18 = $3456 a month.
This is on top of the original budget figure of 9216, which gives a total of 9216 + 3456 = $12672

For energy, note 6 says it is $2.94 per hour worked.
They actually work extra hours as follows: 8 staff x 24 days x 1.5 hours (see above) = 288 extra hours. So we should flex the budget by adding 288 extra hours x 2.94 per hour = $847. Existing budget is $3387, so flexed budget is $3387 + $847 = $4234.