Finding the Fourth Proportional to 3,978.89, 5,968.34 and 1,380

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.89 : 5,968.34 = 1,380 : x
2. Step 2: Convert to fraction form
   3,978.89/5,968.34 = 1,380/x
3. Step 3: Cross multiply
   3,978.89x = 5,968.34 × 1,380
4. Step 4: Simplify right side
   3,978.89x = 8,236,302.30
5. Step 5: Solve for x
   x = 8,236,302.30/3,978.89
6. Step 6: Final answer
   x = 2,070.00