Finding the Third Proportional to 4,915.69 and 8,117.72

Step by Step Solution

1. Step 1: Write the proportion equation
   4,915.69 : 8,117.72 = 8,117.72 : x
2. Step 2: Convert to fraction form
   4,915.69/8,117.72 = 8,117.72/x
3. Step 3: Cross multiply
   4,915.69x = 8,117.72 × 8,117.72
4. Step 4: Simplify right side
   4,915.69x = 65,897,357.70
5. Step 5: Solve for x
   x = 65,897,357.70/4,915.69
6. Step 6: Final answer
   x = 13,405.52