Finding the Fourth Proportional to 2,109.61, 2,911.23 and 1,213.48

Step by Step Solution

1. Step 1: Write the proportion equation
   2,109.61 : 2,911.23 = 1,213.48 : x
2. Step 2: Convert to fraction form
   2,109.61/2,911.23 = 1,213.48/x
3. Step 3: Cross multiply
   2,109.61x = 2,911.23 × 1,213.48
4. Step 4: Simplify right side
   2,109.61x = 3,532,719.38
5. Step 5: Solve for x
   x = 3,532,719.38/2,109.61
6. Step 6: Final answer
   x = 1,674.58