Finding the Fourth Proportional to 1,408.91, 2,113.12 and 531.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,408.91 : 2,113.12 = 531.50 : x
2. Step 2: Convert to fraction form
   1,408.91/2,113.12 = 531.50/x
3. Step 3: Cross multiply
   1,408.91x = 2,113.12 × 531.50
4. Step 4: Simplify right side
   1,408.91x = 1,123,111.39
5. Step 5: Solve for x
   x = 1,123,111.39/1,408.91
6. Step 6: Final answer
   x = 797.15