Finding the Fourth Proportional to 7,042.18, 9,722.01 and 5,642.50

Step by Step Solution

1. Step 1: Write the proportion equation
   7,042.18 : 9,722.01 = 5,642.50 : x
2. Step 2: Convert to fraction form
   7,042.18/9,722.01 = 5,642.50/x
3. Step 3: Cross multiply
   7,042.18x = 9,722.01 × 5,642.50
4. Step 4: Simplify right side
   7,042.18x = 54,856,441.43
5. Step 5: Solve for x
   x = 54,856,441.43/7,042.18
6. Step 6: Final answer
   x = 7,789.70