Finding the Fourth Proportional to 42,387.76, 63,599.60 and 21,316.72

Step by Step Solution

1. Step 1: Write the proportion equation
   42,387.76 : 63,599.60 = 21,316.72 : x
2. Step 2: Convert to fraction form
   42,387.76/63,599.60 = 21,316.72/x
3. Step 3: Cross multiply
   42,387.76x = 63,599.60 × 21,316.72
4. Step 4: Simplify right side
   42,387.76x = 1,355,734,865.31
5. Step 5: Solve for x
   x = 1,355,734,865.31/42,387.76
6. Step 6: Final answer
   x = 31,984.11