Finding the Fourth Proportional to 12,670.10, 18,994.88 and 5,280.10

Step by Step Solution

1. Step 1: Write the proportion equation
   12,670.10 : 18,994.88 = 5,280.10 : x
2. Step 2: Convert to fraction form
   12,670.10/18,994.88 = 5,280.10/x
3. Step 3: Cross multiply
   12,670.10x = 18,994.88 × 5,280.10
4. Step 4: Simplify right side
   12,670.10x = 100,294,865.89
5. Step 5: Solve for x
   x = 100,294,865.89/12,670.10
6. Step 6: Final answer
   x = 7,915.87