Finding the Fourth Proportional to 13,155.53, 18,155.88 and 7,188.10

Step by Step Solution

1. Step 1: Write the proportion equation
   13,155.53 : 18,155.88 = 7,188.10 : x
2. Step 2: Convert to fraction form
   13,155.53/18,155.88 = 7,188.10/x
3. Step 3: Cross multiply
   13,155.53x = 18,155.88 × 7,188.10
4. Step 4: Simplify right side
   13,155.53x = 130,506,190.25
5. Step 5: Solve for x
   x = 130,506,190.25/13,155.53
6. Step 6: Final answer
   x = 9,920.25