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Finding the Fourth Proportional to 728.72, 1,004.80 and 479.96

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Solution

The fourth proportional to 728.72, 1,004.80 and 479.96 is: 661.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.72 : 1,004.80 = 479.96 : x
  2. Step 2: Convert to fraction form
    728.72/1,004.80 = 479.96/x
  3. Step 3: Cross multiply
    728.72x = 1,004.80 × 479.96
  4. Step 4: Simplify right side
    728.72x = 482,263.81
  5. Step 5: Solve for x
    x = 482,263.81/728.72
  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.