Finding the Fourth Proportional to 42,909.50, 64,364.34 and 18,285.50

Step by Step Solution

1. Step 1: Write the proportion equation
   42,909.50 : 64,364.34 = 18,285.50 : x
2. Step 2: Convert to fraction form
   42,909.50/64,364.34 = 18,285.50/x
3. Step 3: Cross multiply
   42,909.50x = 64,364.34 × 18,285.50
4. Step 4: Simplify right side
   42,909.50x = 1,176,934,139.07
5. Step 5: Solve for x
   x = 1,176,934,139.07/42,909.50
6. Step 6: Final answer
   x = 27,428.29