Finding the Fourth Proportional to 1,139.87, 1,707.53 and 976.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.87 : 1,707.53 = 976.15 : x
2. Step 2: Convert to fraction form
   1,139.87/1,707.53 = 976.15/x
3. Step 3: Cross multiply
   1,139.87x = 1,707.53 × 976.15
4. Step 4: Simplify right side
   1,139.87x = 1,666,808.15
5. Step 5: Solve for x
   x = 1,666,808.15/1,139.87
6. Step 6: Final answer
   x = 1,462.28