Finding the Fourth Proportional to 1,012.16, 1,396.42 and 663.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,012.16 : 1,396.42 = 663.05 : x
2. Step 2: Convert to fraction form
   1,012.16/1,396.42 = 663.05/x
3. Step 3: Cross multiply
   1,012.16x = 1,396.42 × 663.05
4. Step 4: Simplify right side
   1,012.16x = 925,887.64
5. Step 5: Solve for x
   x = 925,887.64/1,012.16
6. Step 6: Final answer
   x = 914.77