Finding the Fourth Proportional to 1,978.71, 2,967.21 and 939.01

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.71 : 2,967.21 = 939.01 : x
2. Step 2: Convert to fraction form
   1,978.71/2,967.21 = 939.01/x
3. Step 3: Cross multiply
   1,978.71x = 2,967.21 × 939.01
4. Step 4: Simplify right side
   1,978.71x = 2,786,235.17
5. Step 5: Solve for x
   x = 2,786,235.17/1,978.71
6. Step 6: Final answer
   x = 1,408.11