Identification of Variable, Fixed, and Mixed Costs

Identify the following as (a) fixed costs, (b) variable costs, or (c) mixed costs:

1. Direct materials

4. Personnel manager’s salary

2. Electricity

5. Factory building rent

3. Operating supplies

Mixed Costs: High-Low Method

Using the high-low method and the following information, compute the monthly variable cost per telephone hour and total fixed costs for Sadiko Corporation

Month

Telephone Hours Used

Telephone Costs

April

96

$4,350

May

93

$4,230

June

105

4,710