Finding the Fourth Proportional to 42,973.34, 64,459.82 and 13,391.20

Step by Step Solution

1. Step 1: Write the proportion equation
   42,973.34 : 64,459.82 = 13,391.20 : x
2. Step 2: Convert to fraction form
   42,973.34/64,459.82 = 13,391.20/x
3. Step 3: Cross multiply
   42,973.34x = 64,459.82 × 13,391.20
4. Step 4: Simplify right side
   42,973.34x = 863,194,213.91
5. Step 5: Solve for x
   x = 863,194,213.91/42,973.34
6. Step 6: Final answer
   x = 20,086.74