Finding the Fourth Proportional to 12,947.84, 17,868.56 and 7,642.65

Step by Step Solution

1. Step 1: Write the proportion equation
   12,947.84 : 17,868.56 = 7,642.65 : x
2. Step 2: Convert to fraction form
   12,947.84/17,868.56 = 7,642.65/x
3. Step 3: Cross multiply
   12,947.84x = 17,868.56 × 7,642.65
4. Step 4: Simplify right side
   12,947.84x = 136,563,111.87
5. Step 5: Solve for x
   x = 136,563,111.87/12,947.84
6. Step 6: Final answer
   x = 10,547.18