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Finding the Fourth Proportional to 387.94, 534.18 and 309.10

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Solution

The fourth proportional to 387.94, 534.18 and 309.10 is: 425.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.94 : 534.18 = 309.10 : x
  2. Step 2: Convert to fraction form
    387.94/534.18 = 309.10/x
  3. Step 3: Cross multiply
    387.94x = 534.18 × 309.10
  4. Step 4: Simplify right side
    387.94x = 165,115.04
  5. Step 5: Solve for x
    x = 165,115.04/387.94
  6. Step 6: Final answer
    x = 425.62

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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.