Finding the Fourth Proportional to 1,314.06, 1,970.56 and 389.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,314.06 : 1,970.56 = 389.31 : x
2. Step 2: Convert to fraction form
   1,314.06/1,970.56 = 389.31/x
3. Step 3: Cross multiply
   1,314.06x = 1,970.56 × 389.31
4. Step 4: Simplify right side
   1,314.06x = 767,158.71
5. Step 5: Solve for x
   x = 767,158.71/1,314.06
6. Step 6: Final answer
   x = 583.81