Finding the Fourth Proportional to 1,199.10, 1,655.52 and 978.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,199.10 : 1,655.52 = 978.58 : x
2. Step 2: Convert to fraction form
   1,199.10/1,655.52 = 978.58/x
3. Step 3: Cross multiply
   1,199.10x = 1,655.52 × 978.58
4. Step 4: Simplify right side
   1,199.10x = 1,620,050.48
5. Step 5: Solve for x
   x = 1,620,050.48/1,199.10
6. Step 6: Final answer
   x = 1,351.06