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Finding the Fourth Proportional to 728.25, 1,004.70 and 479.70

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Solution

The fourth proportional to 728.25, 1,004.70 and 479.70 is: 661.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.25 : 1,004.70 = 479.70 : x
  2. Step 2: Convert to fraction form
    728.25/1,004.70 = 479.70/x
  3. Step 3: Cross multiply
    728.25x = 1,004.70 × 479.70
  4. Step 4: Simplify right side
    728.25x = 481,954.59
  5. Step 5: Solve for x
    x = 481,954.59/728.25
  6. Step 6: Final answer
    x = 661.80

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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.