Finding the Fourth Proportional to 2,152.67, 2,970.74 and 1,221.17

Step by Step Solution

1. Step 1: Write the proportion equation
   2,152.67 : 2,970.74 = 1,221.17 : x
2. Step 2: Convert to fraction form
   2,152.67/2,970.74 = 1,221.17/x
3. Step 3: Cross multiply
   2,152.67x = 2,970.74 × 1,221.17
4. Step 4: Simplify right side
   2,152.67x = 3,627,772.46
5. Step 5: Solve for x
   x = 3,627,772.46/2,152.67
6. Step 6: Final answer
   x = 1,685.24