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Finding the Fourth Proportional to 789.57, 1,089.45 and 509.72

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Solution

The fourth proportional to 789.57, 1,089.45 and 509.72 is: 703.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    789.57 : 1,089.45 = 509.72 : x
  2. Step 2: Convert to fraction form
    789.57/1,089.45 = 509.72/x
  3. Step 3: Cross multiply
    789.57x = 1,089.45 × 509.72
  4. Step 4: Simplify right side
    789.57x = 555,309.01
  5. Step 5: Solve for x
    x = 555,309.01/789.57
  6. Step 6: Final answer
    x = 703.31

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.