a) Determination of Total Maintenance Cost Using High-Low Method:
i) High-Low Method Calculation:
Variable Cost per Unit=Highest Cost−Lowest CostHighest Activity Level−Lowest Activity Level\text{Variable Cost per Unit} = \frac{\text{Highest Cost} – \text{Lowest Cost}}{\text{Highest Activity Level} – \text{Lowest Activity Level}}Variable Cost per Unit=Highest Activity Level−Lowest Activity LevelHighest Cost−Lowest Cost Variable Cost per Hour=(22,575−18,125)(1,425−1,175)=4,450250=GH¢13.32 per hour\text{Variable Cost per Hour} = \frac{(22,575 – 18,125)}{(1,425 – 1,175)} = \frac{4,450}{250} = GH¢13.32 \text{ per hour}Variable Cost per Hour=(1,425−1,175)(22,575−18,125)=2504,450=GH¢13.32 per hour
- Total Fixed Cost (Activity exceeds 1,400 hours):
Total Fixed Cost=Total Cost at Maximum Activity Level−(Variable Cost per Hour×Maximum Activity Level)\text{Total Fixed Cost} = \text{Total Cost at Maximum Activity Level} – (\text{Variable Cost per Hour} \times \text{Maximum Activity Level})Total Fixed Cost=Total Cost at Maximum Activity Level−(Variable Cost per Hour×Maximum Activity Level) Total Fixed Cost=GH¢22,575−(GH¢13.32×1,425)=GH¢22,575−GH¢18,981=GH¢3,594\text{Total Fixed Cost} = GH¢22,575 – (GH¢13.32 \times 1,425) = GH¢22,575 – GH¢18,981 = GH¢3,594Total Fixed Cost=GH¢22,575−(GH¢13.32×1,425)=GH¢22,575−GH¢18,981=GH¢3,594
- Total Fixed Cost (Activity below 1,400 hours):
Total Fixed Cost=GH¢3,594−GH¢1,120=GH¢2,474\text{Total Fixed Cost} = GH¢3,594 – GH¢1,120 = GH¢2,474Total Fixed Cost=GH¢3,594−GH¢1,120=GH¢2,474
ii) Maintenance Cost Calculation:
- For May 2018 (1,520 hours):
Maintenance Cost=Fixed Cost+(Variable Cost per Hour×Maintenance Hours)\text{Maintenance Cost} = \text{Fixed Cost} + (\text{Variable Cost per Hour} \times \text{Maintenance Hours})Maintenance Cost=Fixed Cost+(Variable Cost per Hour×Maintenance Hours) Maintenance Cost=GH¢3,594+(GH¢13.32×1,520)=GH¢3,594+GH¢20,246.40=GH¢23,840.40\text{Maintenance Cost} = GH¢3,594 + (GH¢13.32 \times 1,520) = GH¢3,594 + GH¢20,246.40 = GH¢23,840.40Maintenance Cost=GH¢3,594+(GH¢13.32×1,520)=GH¢3,594+GH¢20,246.40=GH¢23,840.40
- For June 2018 (1,075 hours):
Maintenance Cost=GH¢2,474+(GH¢13.32×1,075)=GH¢2,474+GH¢14,319=GH¢16,793\text{Maintenance Cost} = GH¢2,474 + (GH¢13.32 \times 1,075) = GH¢2,474 + GH¢14,319 = GH¢16,793Maintenance Cost=GH¢2,474+(GH¢13.32×1,075)=GH¢2,474+GH¢14,319=GH¢16,793
b) Calculations for May:
i) Break-Even Point:
- Break-Even Point in Units:
BEP (Units)=Total Fixed CostContribution per Unit\text{BEP (Units)} = \frac{\text{Total Fixed Cost}}{\text{Contribution per Unit}}BEP (Units)=Contribution per UnitTotal Fixed Cost BEP (Units)=GH¢35,000+GH¢3,594GH¢1,000−(GH¢644.39+GH¢13.32)=GH¢38,594GH¢342.29≈113 cars\text{BEP (Units)} = \frac{GH¢35,000 + GH¢3,594}{GH¢1,000 – (GH¢644.39 + GH¢13.32)} = \frac{GH¢38,594}{GH¢342.29} \approx 113 \text{ cars}BEP (Units)=GH¢1,000−(GH¢644.39+GH¢13.32)GH¢35,000+GH¢3,594=GH¢342.29GH¢38,594≈113 cars
- Break-Even Point in Sales Value:
BEP (Sales Value)=BEP (Units)×Selling Price per Unit\text{BEP (Sales Value)} = \text{BEP (Units)} \times \text{Selling Price per Unit}BEP (Sales Value)=BEP (Units)×Selling Price per Unit BEP (Sales Value)=113×GH¢1,000=GH¢113,000\text{BEP (Sales Value)} = 113 \times GH¢1,000 = GH¢113,000BEP (Sales Value)=113×GH¢1,000=GH¢113,000
ii) Sales Level for After-Tax Profit of GH¢21,150:
Required Sales Level=Total Fixed Cost+ProfitContribution Margin Ratio\text{Required Sales Level} = \frac{\text{Total Fixed Cost} + \text{Profit}}{\text{Contribution Margin Ratio}}Required Sales Level=Contribution Margin RatioTotal Fixed Cost+Profit Required Sales Level=GH¢38,594+GH¢21,150/(1−0.25)0.34229=GH¢38,594+GH¢28,2000.34229=GH¢195,138.63\text{Required Sales Level} = \frac{GH¢38,594 + GH¢21,150/(1 – 0.25)}{0.34229} = \frac{GH¢38,594 + GH¢28,200}{0.34229} = GH¢195,138.63Required Sales Level=0.34229GH¢38,594+GH¢21,150/(1−0.25)=0.34229GH¢38,594+GH¢28,200=GH¢195,138.63
iii) Margin of Safety:
- Margin of Safety Calculation:
Margin of Safety (%)=Budgeted Sales Level−Break-Even SalesBudgeted Sales Level×100\text{Margin of Safety (\%)} = \frac{\text{Budgeted Sales Level} – \text{Break-Even Sales}}{\text{Budgeted Sales Level}} \times 100Margin of Safety (%)=Budgeted Sales LevelBudgeted Sales Level−Break-Even Sales×100 Margin of Safety (%)=GH¢195,138.63−GH¢113,000GH¢195,138.63×100=42.10%\text{Margin of Safety (\%)} = \frac{GH¢195,138.63 – GH¢113,000}{GH¢195,138.63} \times 100 = 42.10\%Margin of Safety (%)=GH¢195,138.63GH¢195,138.63−GH¢113,000×100=42.10%