Finding the Fourth Proportional to 89,880.56, 134,834.88 and 39,978.08

Step by Step Solution

1. Step 1: Write the proportion equation
   89,880.56 : 134,834.88 = 39,978.08 : x
2. Step 2: Convert to fraction form
   89,880.56/134,834.88 = 39,978.08/x
3. Step 3: Cross multiply
   89,880.56x = 134,834.88 × 39,978.08
4. Step 4: Simplify right side
   89,880.56x = 5,390,439,619.43
5. Step 5: Solve for x
   x = 5,390,439,619.43/89,880.56
6. Step 6: Final answer
   x = 59,973.36