ANSWERS TO QUESTIONS
1. (a) Cost behavior analysis is the study of how specific costs respond to changes in the level of activity
within a company.
(b) Cost behavior analysis is important to management in planning business operations and in deciding
between alternative courses of action.
2. (a) The activity index identifies the activity that causes changes in the behavior of costs. Once the
index is determined, it is possible to classify the behavior of costs in response to changes in
activity levels into three categories: variable, fixed, or mixed.
(b) Variable costs may be defined in total or on a per-unit basis. Variable costs in total vary directly
and proportionately with changes in the activity level. Variable costs per unit remain the
same at every level of activity.
3. Fixed costs remain the same in total regardless of changes in the activity level. In contrast, fixed
costs per unit vary inversely with activity. As volume increases, fixed costs per unit decline and vice
versa.
4. (a) The relevant range is the range of activity over which a company expects to operate during
the year.
(b) Disagree. The behavior of both fixed and variable costs are linear only over a certain range
of activity. CVP analysis is based on the assumption that both fixed and variable costs
remain linear within the relevant range.
5. This is true. Most companies operate within the relevant range. Within this range, it is possible to
establish a linear (straight-line) relationship for both variable and fixed costs. If a relevant range
cannot be established, segregation of costs into fixed and variable becomes extremely difficult.
6. Apartment rent is fixed because the cost per month remains the same regardless of how much Adam
uses the apartment. Rent on a Hertz rental truck is a mixed cost because the cost usually includes a
per day charge (a fixed cost) plus an activity charge based on miles driven (a variable cost).
7. For CVP analysis, mixed costs must be classified into their fixed and variable elements. One approach
to the classification of mixed costs is the high-low method.
8. Variable cost per unit is $1.30, or [($165,000 – $100,000) ÷ (90,000 – 40,000)]. At any level of activity,
fixed costs are $48,000 per month [$165,000 – (90,000 X $1.30)].
9. No. Only two of the basic components of cost-volume-profit (CVP) analysis, unit selling prices and
variable cost per unit, relate to unit data. The other components, volume, total fixed costs, and
sales mix, are not based on per-unit amounts.
10. There is no truth in Faye’s statement. Contribution margin is sales less variable costs. It is the
revenue that remains to cover fixed costs and to produce income (profit) for the company.
11. Contribution margin is $14 ($40 – $26). The contribution margin ratio is 35% ($14 ÷ $40).