Finding the Fourth Proportional to 9,906.84, 13,670.64 and 5,715.36

Step by Step Solution

1. Step 1: Write the proportion equation
   9,906.84 : 13,670.64 = 5,715.36 : x
2. Step 2: Convert to fraction form
   9,906.84/13,670.64 = 5,715.36/x
3. Step 3: Cross multiply
   9,906.84x = 13,670.64 × 5,715.36
4. Step 4: Simplify right side
   9,906.84x = 78,132,629.03
5. Step 5: Solve for x
   x = 78,132,629.03/9,906.84
6. Step 6: Final answer
   x = 7,886.74