Finding the Fourth Proportional to 1,085.50, 1,628.52 and 316

Step by Step Solution

1. Step 1: Write the proportion equation
   1,085.50 : 1,628.52 = 316 : x
2. Step 2: Convert to fraction form
   1,085.50/1,628.52 = 316/x
3. Step 3: Cross multiply
   1,085.50x = 1,628.52 × 316
4. Step 4: Simplify right side
   1,085.50x = 514,612.32
5. Step 5: Solve for x
   x = 514,612.32/1,085.50
6. Step 6: Final answer
   x = 474.08