Finding the Fourth Proportional to 12,690.16, 17,510.70 and 7,380.88

Step by Step Solution

1. Step 1: Write the proportion equation
   12,690.16 : 17,510.70 = 7,380.88 : x
2. Step 2: Convert to fraction form
   12,690.16/17,510.70 = 7,380.88/x
3. Step 3: Cross multiply
   12,690.16x = 17,510.70 × 7,380.88
4. Step 4: Simplify right side
   12,690.16x = 129,244,375.42
5. Step 5: Solve for x
   x = 129,244,375.42/12,690.16
6. Step 6: Final answer
   x = 10,184.61