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Finding the Fourth Proportional to 864.20, 1,296.35 and 287.07

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Solution

The fourth proportional to 864.20, 1,296.35 and 287.07 is: 430.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    864.20 : 1,296.35 = 287.07 : x
  2. Step 2: Convert to fraction form
    864.20/1,296.35 = 287.07/x
  3. Step 3: Cross multiply
    864.20x = 1,296.35 × 287.07
  4. Step 4: Simplify right side
    864.20x = 372,141.76
  5. Step 5: Solve for x
    x = 372,141.76/864.20
  6. Step 6: Final answer
    x = 430.62

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.