Finding the Fourth Proportional to 1,372.13, 1,892.22 and 978.47

Step by Step Solution

1. Step 1: Write the proportion equation
   1,372.13 : 1,892.22 = 978.47 : x
2. Step 2: Convert to fraction form
   1,372.13/1,892.22 = 978.47/x
3. Step 3: Cross multiply
   1,372.13x = 1,892.22 × 978.47
4. Step 4: Simplify right side
   1,372.13x = 1,851,480.50
5. Step 5: Solve for x
   x = 1,851,480.50/1,372.13
6. Step 6: Final answer
   x = 1,349.35