Finding the Fourth Proportional to 13,510.89, 18,641.74 and 7,920.81

Step by Step Solution

1. Step 1: Write the proportion equation
   13,510.89 : 18,641.74 = 7,920.81 : x
2. Step 2: Convert to fraction form
   13,510.89/18,641.74 = 7,920.81/x
3. Step 3: Cross multiply
   13,510.89x = 18,641.74 × 7,920.81
4. Step 4: Simplify right side
   13,510.89x = 147,657,680.61
5. Step 5: Solve for x
   x = 147,657,680.61/13,510.89
6. Step 6: Final answer
   x = 10,928.79