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Finding the Fourth Proportional to 728.84, 1,005.80 and 397.26

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Solution

The fourth proportional to 728.84, 1,005.80 and 397.26 is: 548.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.84 : 1,005.80 = 397.26 : x
  2. Step 2: Convert to fraction form
    728.84/1,005.80 = 397.26/x
  3. Step 3: Cross multiply
    728.84x = 1,005.80 × 397.26
  4. Step 4: Simplify right side
    728.84x = 399,564.11
  5. Step 5: Solve for x
    x = 399,564.11/728.84
  6. Step 6: Final answer
    x = 548.22

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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.