Finding the Fourth Proportional to 136,780.72, 205,105.20 and 64,673.56

Step by Step Solution

1. Step 1: Write the proportion equation
   136,780.72 : 205,105.20 = 64,673.56 : x
2. Step 2: Convert to fraction form
   136,780.72/205,105.20 = 64,673.56/x
3. Step 3: Cross multiply
   136,780.72x = 205,105.20 × 64,673.56
4. Step 4: Simplify right side
   136,780.72x = 13,264,883,458.51
5. Step 5: Solve for x
   x = 13,264,883,458.51/136,780.72
6. Step 6: Final answer
   x = 96,979.19