Finding the Fourth Proportional to 1,185.21, 1,777.83 and 319.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,185.21 : 1,777.83 = 319.50 : x
2. Step 2: Convert to fraction form
   1,185.21/1,777.83 = 319.50/x
3. Step 3: Cross multiply
   1,185.21x = 1,777.83 × 319.50
4. Step 4: Simplify right side
   1,185.21x = 568,016.69
5. Step 5: Solve for x
   x = 568,016.69/1,185.21
6. Step 6: Final answer
   x = 479.25