Finding the Fourth Proportional to 9,920.90, 13,688.34 and 7,935.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,920.90 : 13,688.34 = 7,935.50 : x
2. Step 2: Convert to fraction form
   9,920.90/13,688.34 = 7,935.50/x
3. Step 3: Cross multiply
   9,920.90x = 13,688.34 × 7,935.50
4. Step 4: Simplify right side
   9,920.90x = 108,623,822.07
5. Step 5: Solve for x
   x = 108,623,822.07/9,920.90
6. Step 6: Final answer
   x = 10,948.99