Finding the Fourth Proportional to 1,385.74, 1,913.97 and 1,012.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,385.74 : 1,913.97 = 1,012.12 : x
2. Step 2: Convert to fraction form
   1,385.74/1,913.97 = 1,012.12/x
3. Step 3: Cross multiply
   1,385.74x = 1,913.97 × 1,012.12
4. Step 4: Simplify right side
   1,385.74x = 1,937,167.32
5. Step 5: Solve for x
   x = 1,937,167.32/1,385.74
6. Step 6: Final answer
   x = 1,397.93