Finding the Fourth Proportional to 1,403.55, 1,936.18 and 978.00

Step by Step Solution

1. Step 1: Write the proportion equation
   1,403.55 : 1,936.18 = 978.00 : x
2. Step 2: Convert to fraction form
   1,403.55/1,936.18 = 978.00/x
3. Step 3: Cross multiply
   1,403.55x = 1,936.18 × 978.00
4. Step 4: Simplify right side
   1,403.55x = 1,893,580.70
5. Step 5: Solve for x
   x = 1,893,580.70/1,403.55
6. Step 6: Final answer
   x = 1,349.13