Finding the Fourth Proportional to 1,456.23, 2,008.20 and 978.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,456.23 : 2,008.20 = 978.76 : x
2. Step 2: Convert to fraction form
   1,456.23/2,008.20 = 978.76/x
3. Step 3: Cross multiply
   1,456.23x = 2,008.20 × 978.76
4. Step 4: Simplify right side
   1,456.23x = 1,965,552.01
5. Step 5: Solve for x
   x = 1,965,552.01/1,456.23
6. Step 6: Final answer
   x = 1,349.76