Finding the Fourth Proportional to 42,680.78, 64,019.54 and 11,516.84

Step by Step Solution

1. Step 1: Write the proportion equation
   42,680.78 : 64,019.54 = 11,516.84 : x
2. Step 2: Convert to fraction form
   42,680.78/64,019.54 = 11,516.84/x
3. Step 3: Cross multiply
   42,680.78x = 64,019.54 × 11,516.84
4. Step 4: Simplify right side
   42,680.78x = 737,302,799.05
5. Step 5: Solve for x
   x = 737,302,799.05/42,680.78
6. Step 6: Final answer
   x = 17,274.82