Finding the Fourth Proportional to 42,683.80, 64,016.85 and 12,698.20

Step by Step Solution

1. Step 1: Write the proportion equation
   42,683.80 : 64,016.85 = 12,698.20 : x
2. Step 2: Convert to fraction form
   42,683.80/64,016.85 = 12,698.20/x
3. Step 3: Cross multiply
   42,683.80x = 64,016.85 × 12,698.20
4. Step 4: Simplify right side
   42,683.80x = 812,898,764.67
5. Step 5: Solve for x
   x = 812,898,764.67/42,683.80
6. Step 6: Final answer
   x = 19,044.67