Finding the Fourth Proportional to 1,645.82, 2,271.20 and 899.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,645.82 : 2,271.20 = 899.76 : x
2. Step 2: Convert to fraction form
   1,645.82/2,271.20 = 899.76/x
3. Step 3: Cross multiply
   1,645.82x = 2,271.20 × 899.76
4. Step 4: Simplify right side
   1,645.82x = 2,043,534.91
5. Step 5: Solve for x
   x = 2,043,534.91/1,645.82
6. Step 6: Final answer
   x = 1,241.65