Finding the Fourth Proportional to 42,700.80, 64,057.28 and 13,114.20

Step by Step Solution

1. Step 1: Write the proportion equation
   42,700.80 : 64,057.28 = 13,114.20 : x
2. Step 2: Convert to fraction form
   42,700.80/64,057.28 = 13,114.20/x
3. Step 3: Cross multiply
   42,700.80x = 64,057.28 × 13,114.20
4. Step 4: Simplify right side
   42,700.80x = 840,059,915.81
5. Step 5: Solve for x
   x = 840,059,915.81/42,700.80
6. Step 6: Final answer
   x = 19,673.17