Finding the Fourth Proportional to 42,913.69, 64,384.50 and 20,729.61

Step by Step Solution

1. Step 1: Write the proportion equation
   42,913.69 : 64,384.50 = 20,729.61 : x
2. Step 2: Convert to fraction form
   42,913.69/64,384.50 = 20,729.61/x
3. Step 3: Cross multiply
   42,913.69x = 64,384.50 × 20,729.61
4. Step 4: Simplify right side
   42,913.69x = 1,334,665,575.05
5. Step 5: Solve for x
   x = 1,334,665,575.05/42,913.69
6. Step 6: Final answer
   x = 31,101.16