Finding the Fourth Proportional to 153,388.71, 211,674.72 and 85,404.21

Step by Step Solution

1. Step 1: Write the proportion equation
   153,388.71 : 211,674.72 = 85,404.21 : x
2. Step 2: Convert to fraction form
   153,388.71/211,674.72 = 85,404.21/x
3. Step 3: Cross multiply
   153,388.71x = 211,674.72 × 85,404.21
4. Step 4: Simplify right side
   153,388.71x = 18,077,912,238.57
5. Step 5: Solve for x
   x = 18,077,912,238.57/153,388.71
6. Step 6: Final answer
   x = 117,856.86