Finding the Fourth Proportional to 128,786,606.08, 177,709,374.72 and 87,061,456.40

Step by Step Solution

1. Step 1: Write the proportion equation
   128,786,606.08 : 177,709,374.72 = 87,061,456.40 : x
2. Step 2: Convert to fraction form
   128,786,606.08/177,709,374.72 = 87,061,456.40/x
3. Step 3: Cross multiply
   128,786,606.08x = 177,709,374.72 × 87,061,456.40
4. Step 4: Simplify right side
   128,786,606.08x = 15,471,636,979,056,544
5. Step 5: Solve for x
   x = 15,471,636,979,056,544/128,786,606.08
6. Step 6: Final answer
   x = 120,133,897.85