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Finding the Fourth Proportional to 864.32, 1,296.48 and 287.20

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Solution

The fourth proportional to 864.32, 1,296.48 and 287.20 is: 430.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    864.32 : 1,296.48 = 287.20 : x
  2. Step 2: Convert to fraction form
    864.32/1,296.48 = 287.20/x
  3. Step 3: Cross multiply
    864.32x = 1,296.48 × 287.20
  4. Step 4: Simplify right side
    864.32x = 372,349.06
  5. Step 5: Solve for x
    x = 372,349.06/864.32
  6. Step 6: Final answer
    x = 430.80

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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.