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Finding the Fourth Proportional to 728.64, 1,005.54 and 397.10

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Solution

The fourth proportional to 728.64, 1,005.54 and 397.10 is: 548.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.64 : 1,005.54 = 397.10 : x
  2. Step 2: Convert to fraction form
    728.64/1,005.54 = 397.10/x
  3. Step 3: Cross multiply
    728.64x = 1,005.54 × 397.10
  4. Step 4: Simplify right side
    728.64x = 399,294.91
  5. Step 5: Solve for x
    x = 399,294.91/728.64
  6. Step 6: Final answer
    x = 548.00

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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.