Finding the Fourth Proportional to 13,690.32, 18,892.59 and 7,402.70

Step by Step Solution

1. Step 1: Write the proportion equation
   13,690.32 : 18,892.59 = 7,402.70 : x
2. Step 2: Convert to fraction form
   13,690.32/18,892.59 = 7,402.70/x
3. Step 3: Cross multiply
   13,690.32x = 18,892.59 × 7,402.70
4. Step 4: Simplify right side
   13,690.32x = 139,856,081.53
5. Step 5: Solve for x
   x = 139,856,081.53/13,690.32
6. Step 6: Final answer
   x = 10,215.69