Finding the Fourth Proportional to 1,875.10, 2,812.69 and 642.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,875.10 : 2,812.69 = 642.50 : x
2. Step 2: Convert to fraction form
   1,875.10/2,812.69 = 642.50/x
3. Step 3: Cross multiply
   1,875.10x = 2,812.69 × 642.50
4. Step 4: Simplify right side
   1,875.10x = 1,807,153.33
5. Step 5: Solve for x
   x = 1,807,153.33/1,875.10
6. Step 6: Final answer
   x = 963.76