Finding the Fourth Proportional to 1,056.59, 1,458 and 978.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,056.59 : 1,458 = 978.23 : x
2. Step 2: Convert to fraction form
   1,056.59/1,458 = 978.23/x
3. Step 3: Cross multiply
   1,056.59x = 1,458 × 978.23
4. Step 4: Simplify right side
   1,056.59x = 1,426,254.78
5. Step 5: Solve for x
   x = 1,426,254.78/1,056.59
6. Step 6: Final answer
   x = 1,349.86