Finding the Fourth Proportional to 100,513.86, 138,680.82 and 64,724.58

Step by Step Solution

1. Step 1: Write the proportion equation
   100,513.86 : 138,680.82 = 64,724.58 : x
2. Step 2: Convert to fraction form
   100,513.86/138,680.82 = 64,724.58/x
3. Step 3: Cross multiply
   100,513.86x = 138,680.82 × 64,724.58
4. Step 4: Simplify right side
   100,513.86x = 8,976,057,828.56
5. Step 5: Solve for x
   x = 8,976,057,828.56/100,513.86
6. Step 6: Final answer
   x = 89,301.69