Finding the Fourth Proportional to 76,564.40, 105,664.50 and 42,579

Step by Step Solution

1. Step 1: Write the proportion equation
   76,564.40 : 105,664.50 = 42,579 : x
2. Step 2: Convert to fraction form
   76,564.40/105,664.50 = 42,579/x
3. Step 3: Cross multiply
   76,564.40x = 105,664.50 × 42,579
4. Step 4: Simplify right side
   76,564.40x = 4,499,088,745.50
5. Step 5: Solve for x
   x = 4,499,088,745.50/76,564.40
6. Step 6: Final answer
   x = 58,762.15