Finding the Fourth Proportional to 1,320.71, 1,980.45 and 498.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,320.71 : 1,980.45 = 498.76 : x
2. Step 2: Convert to fraction form
   1,320.71/1,980.45 = 498.76/x
3. Step 3: Cross multiply
   1,320.71x = 1,980.45 × 498.76
4. Step 4: Simplify right side
   1,320.71x = 987,764.29
5. Step 5: Solve for x
   x = 987,764.29/1,320.71
6. Step 6: Final answer
   x = 747.91