Finding the Fourth Proportional to 12,838.64, 17,715.58 and 7,172.69

Step by Step Solution

1. Step 1: Write the proportion equation
   12,838.64 : 17,715.58 = 7,172.69 : x
2. Step 2: Convert to fraction form
   12,838.64/17,715.58 = 7,172.69/x
3. Step 3: Cross multiply
   12,838.64x = 17,715.58 × 7,172.69
4. Step 4: Simplify right side
   12,838.64x = 127,068,363.51
5. Step 5: Solve for x
   x = 127,068,363.51/12,838.64
6. Step 6: Final answer
   x = 9,897.34