Finding the Fourth Proportional to 1,238.98, 1,856.55 and 507.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,238.98 : 1,856.55 = 507.94 : x
2. Step 2: Convert to fraction form
   1,238.98/1,856.55 = 507.94/x
3. Step 3: Cross multiply
   1,238.98x = 1,856.55 × 507.94
4. Step 4: Simplify right side
   1,238.98x = 943,016.01
5. Step 5: Solve for x
   x = 943,016.01/1,238.98
6. Step 6: Final answer
   x = 761.12