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Finding the Fourth Proportional to 864.41, 1,296.40 and 287.21

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Solution

The fourth proportional to 864.41, 1,296.40 and 287.21 is: 430.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    864.41 : 1,296.40 = 287.21 : x
  2. Step 2: Convert to fraction form
    864.41/1,296.40 = 287.21/x
  3. Step 3: Cross multiply
    864.41x = 1,296.40 × 287.21
  4. Step 4: Simplify right side
    864.41x = 372,339.04
  5. Step 5: Solve for x
    x = 372,339.04/864.41
  6. Step 6: Final answer
    x = 430.74

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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.