Finding the Fourth Proportional to 76,472, 105,485.60 and 48,128.48

Step by Step Solution

1. Step 1: Write the proportion equation
   76,472 : 105,485.60 = 48,128.48 : x
2. Step 2: Convert to fraction form
   76,472/105,485.60 = 48,128.48/x
3. Step 3: Cross multiply
   76,472x = 105,485.60 × 48,128.48
4. Step 4: Simplify right side
   76,472x = 5,076,861,589.89
5. Step 5: Solve for x
   x = 5,076,861,589.89/76,472
6. Step 6: Final answer
   x = 66,388.50