Finding the Fourth Proportional to 1,428.99, 1,970.45 and 930.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,428.99 : 1,970.45 = 930.71 : x
2. Step 2: Convert to fraction form
   1,428.99/1,970.45 = 930.71/x
3. Step 3: Cross multiply
   1,428.99x = 1,970.45 × 930.71
4. Step 4: Simplify right side
   1,428.99x = 1,833,917.52
5. Step 5: Solve for x
   x = 1,833,917.52/1,428.99
6. Step 6: Final answer
   x = 1,283.37