Finding the Fourth Proportional to 1,019.87, 1,407.42 and 554.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.87 : 1,407.42 = 554.12 : x
2. Step 2: Convert to fraction form
   1,019.87/1,407.42 = 554.12/x
3. Step 3: Cross multiply
   1,019.87x = 1,407.42 × 554.12
4. Step 4: Simplify right side
   1,019.87x = 779,872.53
5. Step 5: Solve for x
   x = 779,872.53/1,019.87
6. Step 6: Final answer
   x = 764.68