Finding the Fourth Proportional to 13,656.51, 18,845.78 and 7,688.16

Step by Step Solution

1. Step 1: Write the proportion equation
   13,656.51 : 18,845.78 = 7,688.16 : x
2. Step 2: Convert to fraction form
   13,656.51/18,845.78 = 7,688.16/x
3. Step 3: Cross multiply
   13,656.51x = 18,845.78 × 7,688.16
4. Step 4: Simplify right side
   13,656.51x = 144,889,333.52
5. Step 5: Solve for x
   x = 144,889,333.52/13,656.51
6. Step 6: Final answer
   x = 10,609.54