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Finding the Fourth Proportional to 728.70, 1,007.55 and 636.48

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Solution

The fourth proportional to 728.70, 1,007.55 and 636.48 is: 880.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.70 : 1,007.55 = 636.48 : x
  2. Step 2: Convert to fraction form
    728.70/1,007.55 = 636.48/x
  3. Step 3: Cross multiply
    728.70x = 1,007.55 × 636.48
  4. Step 4: Simplify right side
    728.70x = 641,285.42
  5. Step 5: Solve for x
    x = 641,285.42/728.70
  6. Step 6: Final answer
    x = 880.04

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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.