Finding the Fourth Proportional to 90,989.08, 136,498.47 and 28,645

Step by Step Solution

1. Step 1: Write the proportion equation
   90,989.08 : 136,498.47 = 28,645 : x
2. Step 2: Convert to fraction form
   90,989.08/136,498.47 = 28,645/x
3. Step 3: Cross multiply
   90,989.08x = 136,498.47 × 28,645
4. Step 4: Simplify right side
   90,989.08x = 3,909,998,673.15
5. Step 5: Solve for x
   x = 3,909,998,673.15/90,989.08
6. Step 6: Final answer
   x = 42,972.18