Finding the Fourth Proportional to 1,070.25, 1,476.72 and 628.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,070.25 : 1,476.72 = 628.20 : x
2. Step 2: Convert to fraction form
   1,070.25/1,476.72 = 628.20/x
3. Step 3: Cross multiply
   1,070.25x = 1,476.72 × 628.20
4. Step 4: Simplify right side
   1,070.25x = 927,675.50
5. Step 5: Solve for x
   x = 927,675.50/1,070.25
6. Step 6: Final answer
   x = 866.78