Finding the Fourth Proportional to 1,020.25, 1,407.98 and 554.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,020.25 : 1,407.98 = 554.53 : x
2. Step 2: Convert to fraction form
   1,020.25/1,407.98 = 554.53/x
3. Step 3: Cross multiply
   1,020.25x = 1,407.98 × 554.53
4. Step 4: Simplify right side
   1,020.25x = 780,767.15
5. Step 5: Solve for x
   x = 780,767.15/1,020.25
6. Step 6: Final answer
   x = 765.27