Finding the Fourth Proportional to 3,985.96, 5,978.96 and 1,679.08

Step by Step Solution

1. Step 1: Write the proportion equation
   3,985.96 : 5,978.96 = 1,679.08 : x
2. Step 2: Convert to fraction form
   3,985.96/5,978.96 = 1,679.08/x
3. Step 3: Cross multiply
   3,985.96x = 5,978.96 × 1,679.08
4. Step 4: Simplify right side
   3,985.96x = 10,039,152.16
5. Step 5: Solve for x
   x = 10,039,152.16/3,985.96
6. Step 6: Final answer
   x = 2,518.63