Finding the Fourth Proportional to 1,399.48, 1,931.96 and 875.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.48 : 1,931.96 = 875.80 : x
2. Step 2: Convert to fraction form
   1,399.48/1,931.96 = 875.80/x
3. Step 3: Cross multiply
   1,399.48x = 1,931.96 × 875.80
4. Step 4: Simplify right side
   1,399.48x = 1,692,010.57
5. Step 5: Solve for x
   x = 1,692,010.57/1,399.48
6. Step 6: Final answer
   x = 1,209.03