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Finding the Fourth Proportional to 528.62, 728.62 and 397.40

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Solution

The fourth proportional to 528.62, 728.62 and 397.40 is: 547.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.62 : 728.62 = 397.40 : x
  2. Step 2: Convert to fraction form
    528.62/728.62 = 397.40/x
  3. Step 3: Cross multiply
    528.62x = 728.62 × 397.40
  4. Step 4: Simplify right side
    528.62x = 289,547.96
  5. Step 5: Solve for x
    x = 289,547.96/528.62
  6. Step 6: Final answer
    x = 547.75

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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.