To calculate the average speed for her whole journey, we can use the formula for average speed:

$\text{Average Speed} = \frac{\text{Total Distance}}{\text{Total Time}}$

We are given two parts of her journey:

1. First part: She jogs 7 km in 45 minutes.

   • Convert 45 minutes to hours:
     $45 \, \text{minutes} = \frac{45}{60} = 0.75 \, \text{hours}$.

   So, for the first part, the speed is: $\text{Speed} = \frac{7 \, \text{km}}{0.75 \, \text{hours}} = 9.33 \, \text{km/hr}.$

2. Second part: She jogs 12 km/h for 30 minutes.

   • Convert 30 minutes to hours:
     $30 \, \text{minutes} = \frac{30}{60} = 0.5 \, \text{hours}$.

   So, the distance covered in the second part is: $\text{Distance} = 12 \, \text{km/hr} \times 0.5 \, \text{hours} = 6 \, \text{km}.$

Total Distance:

$\text{Total Distance} = 7 \, \text{km} + 6 \, \text{km} = 13 \, \text{km}.$

Total Time:

$\text{Total Time} = 0.75 \, \text{hours} + 0.5 \, \text{hours} = 1.25 \, \text{hours}.$

Now, calculate the average speed: $\text{Average Speed} = \frac{13 \, \text{km}}{1.25 \, \text{hours}} = 10.4 \, \text{km/hr}.$

Final Answer:

Her average speed for the whole journey is 10.4 km/hr.

Let me know if you want further details or clarifications. Here are a few related questions you could explore:

1. How does the average speed compare to her speeds in the individual parts of the journey?
2. If she jogged an additional 5 km at the same speeds, how would her average speed change?
3. What happens to the average speed if she jogs 7 km in 30 minutes instead of 45 minutes?
4. How do different times at different speeds affect the overall average speed?
5. What are the effects of increasing the distance in one part of the journey on the average speed?

Tip: When dealing with average speed, always remember that the total distance is the sum of all distances, and the total time is the sum of all times, not the individual speeds or times.