Finding the Fourth Proportional to 71,478.07, 107,074.15 and 42,999.31

Step by Step Solution

1. Step 1: Write the proportion equation
   71,478.07 : 107,074.15 = 42,999.31 : x
2. Step 2: Convert to fraction form
   71,478.07/107,074.15 = 42,999.31/x
3. Step 3: Cross multiply
   71,478.07x = 107,074.15 × 42,999.31
4. Step 4: Simplify right side
   71,478.07x = 4,604,114,568.84
5. Step 5: Solve for x
   x = 4,604,114,568.84/71,478.07
6. Step 6: Final answer
   x = 64,412.97