Finding the Fourth Proportional to 1,287.50, 1,930.10 and 556.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,287.50 : 1,930.10 = 556.67 : x
2. Step 2: Convert to fraction form
   1,287.50/1,930.10 = 556.67/x
3. Step 3: Cross multiply
   1,287.50x = 1,930.10 × 556.67
4. Step 4: Simplify right side
   1,287.50x = 1,074,435.51
5. Step 5: Solve for x
   x = 1,074,435.51/1,287.50
6. Step 6: Final answer
   x = 834.52