Finding the Fourth Proportional to 1,020.72, 1,530.77 and 435.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,020.72 : 1,530.77 = 435.72 : x
2. Step 2: Convert to fraction form
   1,020.72/1,530.77 = 435.72/x
3. Step 3: Cross multiply
   1,020.72x = 1,530.77 × 435.72
4. Step 4: Simplify right side
   1,020.72x = 666,987.10
5. Step 5: Solve for x
   x = 666,987.10/1,020.72
6. Step 6: Final answer
   x = 653.45