Finding the Fourth Proportional to 1,724.02, 2,379.28 and 978.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,724.02 : 2,379.28 = 978.12 : x
2. Step 2: Convert to fraction form
   1,724.02/2,379.28 = 978.12/x
3. Step 3: Cross multiply
   1,724.02x = 2,379.28 × 978.12
4. Step 4: Simplify right side
   1,724.02x = 2,327,221.35
5. Step 5: Solve for x
   x = 2,327,221.35/1,724.02
6. Step 6: Final answer
   x = 1,349.88