Opertaing stating under Marginal costing

@nitishthapa said:
As i looked at your video on operating statement under both costing method you used sales budget , but kaplan text book made me confused , under the marginal costing approach it says for
Budgeted contribution (budgeted production * budgeted contribution/unit),

could you please tell the reason why they using budgeted production instead of budgeted sales.

I have one more question sir,

there is question in kaplan text book

Riki Ltd. produces and sells one product only. The standard cost price for one unit being as follows:

D Mat A- 10 kg at $12/kg – $120
D Mat B- 6 kg at $ 5 /kg – $30
D wages 5 hr at $ 8/hr – $ 40
Fixed prod. o/h – $60
Total standard cost – $250
Std. gross profit – $ 50

Std. selling price -$300

The fixes production overhead included in the standard cost is based on an expected monthly output of 750 units . Riki Ltd. use an absorption costing system.

Actual sales unit is 700 units.

Sales 700 @ $ 320 -$224000
Direct material :
A-7500 kg – $91500
B -7500kg – $ 20300

Direct wages 3400hrs – $ 27880
Fixed production o/h – $ 37000
Total – $ 176680

Gross profit – $47320

Notes: Riki Ltd does not hold any inventories

Required

You are required to reconcile budgeted profit with actual profit for the period., calculating the following variance

Selling price, sales volume, material price, material usage, labour rate, labour efficiency, fixed overhead expenditure and fixed over volume.

My Question- . They are using 750 units to calculate budgeted profit , but there is no mention 750 as budgeted sales, could you please tell why they using 750 as budgeted sales figure, there is not given any units figure except 750 and 700.