"A storage room must be kept at a temperature (T) such that triple the temperature is at least 15° C , but the temperature plus 8 is not more than 20° C . What is the range of safe temperatures?"

Step-by-step solution

From the given problem, the temperature T must satisfy two conditions. The first condition is that triple the temperature is at least 15 . This can be written as the inequality: 3T 15 Dividing both sides by 3 yields: T 5 The second condition is that the temperature plus 8 is not more than 20 . This can be written as the inequality: T + 8 20 Subtracting 8 from both sides yields: T 12 Combining the two inequalities gives the range of safe temperatures: 5 T 12 In interval notation, this represents the closed interval