Finding the Fourth Proportional to 2,212.45, 3,320.18 and 913.91

Step by Step Solution

1. Step 1: Write the proportion equation
   2,212.45 : 3,320.18 = 913.91 : x
2. Step 2: Convert to fraction form
   2,212.45/3,320.18 = 913.91/x
3. Step 3: Cross multiply
   2,212.45x = 3,320.18 × 913.91
4. Step 4: Simplify right side
   2,212.45x = 3,034,345.70
5. Step 5: Solve for x
   x = 3,034,345.70/2,212.45
6. Step 6: Final answer
   x = 1,371.49