Finding the Fourth Proportional to 42,688.56, 64,042.32 and 13,108.98

Step by Step Solution

1. Step 1: Write the proportion equation
   42,688.56 : 64,042.32 = 13,108.98 : x
2. Step 2: Convert to fraction form
   42,688.56/64,042.32 = 13,108.98/x
3. Step 3: Cross multiply
   42,688.56x = 64,042.32 × 13,108.98
4. Step 4: Simplify right side
   42,688.56x = 839,529,492.03
5. Step 5: Solve for x
   x = 839,529,492.03/42,688.56
6. Step 6: Final answer
   x = 19,666.38