Finding the Fourth Proportional to 13,978.84, 20,971.88 and 4,117.78

Step by Step Solution

1. Step 1: Write the proportion equation
   13,978.84 : 20,971.88 = 4,117.78 : x
2. Step 2: Convert to fraction form
   13,978.84/20,971.88 = 4,117.78/x
3. Step 3: Cross multiply
   13,978.84x = 20,971.88 × 4,117.78
4. Step 4: Simplify right side
   13,978.84x = 86,357,588.03
5. Step 5: Solve for x
   x = 86,357,588.03/13,978.84
6. Step 6: Final answer
   x = 6,177.74