Finding the Fourth Proportional to 39,513.57, 54,528.71 and 21,608.59

Step by Step Solution

1. Step 1: Write the proportion equation
   39,513.57 : 54,528.71 = 21,608.59 : x
2. Step 2: Convert to fraction form
   39,513.57/54,528.71 = 21,608.59/x
3. Step 3: Cross multiply
   39,513.57x = 54,528.71 × 21,608.59
4. Step 4: Simplify right side
   39,513.57x = 1,178,288,264.98
5. Step 5: Solve for x
   x = 1,178,288,264.98/39,513.57
6. Step 6: Final answer
   x = 29,819.84