Finding the Fourth Proportional to 1,428.17, 1,971.81 and 1,098.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,428.17 : 1,971.81 = 1,098.32 : x
2. Step 2: Convert to fraction form
   1,428.17/1,971.81 = 1,098.32/x
3. Step 3: Cross multiply
   1,428.17x = 1,971.81 × 1,098.32
4. Step 4: Simplify right side
   1,428.17x = 2,165,668.50
5. Step 5: Solve for x
   x = 2,165,668.50/1,428.17
6. Step 6: Final answer
   x = 1,516.40