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Finding the Fourth Proportional to 630.25, 869.96 and 391.16

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Solution

The fourth proportional to 630.25, 869.96 and 391.16 is: 539.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.25 : 869.96 = 391.16 : x
  2. Step 2: Convert to fraction form
    630.25/869.96 = 391.16/x
  3. Step 3: Cross multiply
    630.25x = 869.96 × 391.16
  4. Step 4: Simplify right side
    630.25x = 340,293.55
  5. Step 5: Solve for x
    x = 340,293.55/630.25
  6. Step 6: Final answer
    x = 539.93

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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.