Finding the Fourth Proportional to 13,109.86, 18,091.44 and 7,141.50

Step by Step Solution

1. Step 1: Write the proportion equation
   13,109.86 : 18,091.44 = 7,141.50 : x
2. Step 2: Convert to fraction form
   13,109.86/18,091.44 = 7,141.50/x
3. Step 3: Cross multiply
   13,109.86x = 18,091.44 × 7,141.50
4. Step 4: Simplify right side
   13,109.86x = 129,200,018.76
5. Step 5: Solve for x
   x = 129,200,018.76/13,109.86
6. Step 6: Final answer
   x = 9,855.18