Finding the Fourth Proportional to 1,430.30, 1,973.93 and 840.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,430.30 : 1,973.93 = 840.72 : x
2. Step 2: Convert to fraction form
   1,430.30/1,973.93 = 840.72/x
3. Step 3: Cross multiply
   1,430.30x = 1,973.93 × 840.72
4. Step 4: Simplify right side
   1,430.30x = 1,659,522.43
5. Step 5: Solve for x
   x = 1,659,522.43/1,430.30
6. Step 6: Final answer
   x = 1,160.26