Finding the Fourth Proportional to 287,106.50, 430,663.59 and 90,114.50

Step by Step Solution

1. Step 1: Write the proportion equation
   287,106.50 : 430,663.59 = 90,114.50 : x
2. Step 2: Convert to fraction form
   287,106.50/430,663.59 = 90,114.50/x
3. Step 3: Cross multiply
   287,106.50x = 430,663.59 × 90,114.50
4. Step 4: Simplify right side
   287,106.50x = 38,809,034,081.06
5. Step 5: Solve for x
   x = 38,809,034,081.06/287,106.50
6. Step 6: Final answer
   x = 135,172.96