Venkatalakshmi owns a flour mill. It takes 10 seconds for the roller mill to start running. Once it is running, each kg of grain takes 8 seconds to grind into powder. Which of the expressions below describes the time taken to complete grind 'y' kg of grain, assuming the machine is off initially?
Explanation
The chapter explains that the total time consists of two parts: (1) the fixed startup time of 10 seconds, and (2) the grinding time which is 8 seconds per kg multiplied by y kg. So total time = 10 + 8 × y. This follows the pattern shown in Example 3 where total cost = cost of coconuts + cost of jaggery.
Solution Steps
Step 1: Identify fixed time = 10 seconds (startup time)
Step 2: Identify variable time = 8 seconds per kg × y kg = 8y seconds
Step 3: Total time = fixed time + variable time = 10 + 8y