Finding the Fourth Proportional to 153,628.72, 211,887.45 and 99,930.89

Step by Step Solution

1. Step 1: Write the proportion equation
   153,628.72 : 211,887.45 = 99,930.89 : x
2. Step 2: Convert to fraction form
   153,628.72/211,887.45 = 99,930.89/x
3. Step 3: Cross multiply
   153,628.72x = 211,887.45 × 99,930.89
4. Step 4: Simplify right side
   153,628.72x = 21,174,100,648.72
5. Step 5: Solve for x
   x = 21,174,100,648.72/153,628.72
6. Step 6: Final answer
   x = 137,826.45