Finding the Fourth Proportional to 1,109.62, 1,670.83 and 916.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.62 : 1,670.83 = 916.48 : x
2. Step 2: Convert to fraction form
   1,109.62/1,670.83 = 916.48/x
3. Step 3: Cross multiply
   1,109.62x = 1,670.83 × 916.48
4. Step 4: Simplify right side
   1,109.62x = 1,531,282.28
5. Step 5: Solve for x
   x = 1,531,282.28/1,109.62
6. Step 6: Final answer
   x = 1,380.01