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Finding the Fourth Proportional to 728.29, 1,089.25 and 419.38

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Solution

The fourth proportional to 728.29, 1,089.25 and 419.38 is: 627.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.29 : 1,089.25 = 419.38 : x
  2. Step 2: Convert to fraction form
    728.29/1,089.25 = 419.38/x
  3. Step 3: Cross multiply
    728.29x = 1,089.25 × 419.38
  4. Step 4: Simplify right side
    728.29x = 456,805.89
  5. Step 5: Solve for x
    x = 456,805.89/728.29
  6. Step 6: Final answer
    x = 627.23

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.