Finding the Fourth Proportional to 1,564.86, 2,157.78 and 1,066.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,564.86 : 2,157.78 = 1,066.50 : x
2. Step 2: Convert to fraction form
   1,564.86/2,157.78 = 1,066.50/x
3. Step 3: Cross multiply
   1,564.86x = 2,157.78 × 1,066.50
4. Step 4: Simplify right side
   1,564.86x = 2,301,272.37
5. Step 5: Solve for x
   x = 2,301,272.37/1,564.86
6. Step 6: Final answer
   x = 1,470.59