Finding the Fourth Proportional to 1,978.86, 2,968.22 and 939.36

Step by Step Solution

1. Step 1: Write the proportion equation
   1,978.86 : 2,968.22 = 939.36 : x
2. Step 2: Convert to fraction form
   1,978.86/2,968.22 = 939.36/x
3. Step 3: Cross multiply
   1,978.86x = 2,968.22 × 939.36
4. Step 4: Simplify right side
   1,978.86x = 2,788,227.14
5. Step 5: Solve for x
   x = 2,788,227.14/1,978.86
6. Step 6: Final answer
   x = 1,409.01