Finding the Fourth Proportional to 1,018.22, 1,404.91 and 620.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,018.22 : 1,404.91 = 620.09 : x
2. Step 2: Convert to fraction form
   1,018.22/1,404.91 = 620.09/x
3. Step 3: Cross multiply
   1,018.22x = 1,404.91 × 620.09
4. Step 4: Simplify right side
   1,018.22x = 871,164.39
5. Step 5: Solve for x
   x = 871,164.39/1,018.22
6. Step 6: Final answer
   x = 855.58