Finding the Fourth Proportional to 9,911.74, 13,678.62 and 5,663.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,911.74 : 13,678.62 = 5,663.50 : x
2. Step 2: Convert to fraction form
   9,911.74/13,678.62 = 5,663.50/x
3. Step 3: Cross multiply
   9,911.74x = 13,678.62 × 5,663.50
4. Step 4: Simplify right side
   9,911.74x = 77,468,864.37
5. Step 5: Solve for x
   x = 77,468,864.37/9,911.74
6. Step 6: Final answer
   x = 7,815.87