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Finding the Fourth Proportional to 728.66, 1,005.56 and 397.10

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Solution

The fourth proportional to 728.66, 1,005.56 and 397.10 is: 548.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.66 : 1,005.56 = 397.10 : x
  2. Step 2: Convert to fraction form
    728.66/1,005.56 = 397.10/x
  3. Step 3: Cross multiply
    728.66x = 1,005.56 × 397.10
  4. Step 4: Simplify right side
    728.66x = 399,307.88
  5. Step 5: Solve for x
    x = 399,307.88/728.66
  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.