Finding the Fourth Proportional to 1,258.74, 1,733.50 and 978.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,258.74 : 1,733.50 = 978.48 : x
2. Step 2: Convert to fraction form
   1,258.74/1,733.50 = 978.48/x
3. Step 3: Cross multiply
   1,258.74x = 1,733.50 × 978.48
4. Step 4: Simplify right side
   1,258.74x = 1,696,196.30
5. Step 5: Solve for x
   x = 1,696,196.30/1,258.74
6. Step 6: Final answer
   x = 1,347.54