Finding the Fourth Proportional to 315,042.72, 472,421.93 and 90,351.57

Step by Step Solution

1. Step 1: Write the proportion equation
   315,042.72 : 472,421.93 = 90,351.57 : x
2. Step 2: Convert to fraction form
   315,042.72/472,421.93 = 90,351.57/x
3. Step 3: Cross multiply
   315,042.72x = 472,421.93 × 90,351.57
4. Step 4: Simplify right side
   315,042.72x = 42,684,062,626.17
5. Step 5: Solve for x
   x = 42,684,062,626.17/315,042.72
6. Step 6: Final answer
   x = 135,486.59