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Finding the Fourth Proportional to 728.60, 1,004.68 and 635.20

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Solution

The fourth proportional to 728.60, 1,004.68 and 635.20 is: 875.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.60 : 1,004.68 = 635.20 : x
  2. Step 2: Convert to fraction form
    728.60/1,004.68 = 635.20/x
  3. Step 3: Cross multiply
    728.60x = 1,004.68 × 635.20
  4. Step 4: Simplify right side
    728.60x = 638,172.74
  5. Step 5: Solve for x
    x = 638,172.74/728.60
  6. Step 6: Final answer
    x = 875.89

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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.