Finding the Fourth Proportional to 1,039.53, 1,434.56 and 620.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,039.53 : 1,434.56 = 620.12 : x
2. Step 2: Convert to fraction form
   1,039.53/1,434.56 = 620.12/x
3. Step 3: Cross multiply
   1,039.53x = 1,434.56 × 620.12
4. Step 4: Simplify right side
   1,039.53x = 889,599.35
5. Step 5: Solve for x
   x = 889,599.35/1,039.53
6. Step 6: Final answer
   x = 855.77