Finding the Fourth Proportional to 1,610.40, 2,221.72 and 947.01

Step by Step Solution

1. Step 1: Write the proportion equation
   1,610.40 : 2,221.72 = 947.01 : x
2. Step 2: Convert to fraction form
   1,610.40/2,221.72 = 947.01/x
3. Step 3: Cross multiply
   1,610.40x = 2,221.72 × 947.01
4. Step 4: Simplify right side
   1,610.40x = 2,103,991.06
5. Step 5: Solve for x
   x = 2,103,991.06/1,610.40
6. Step 6: Final answer
   x = 1,306.50