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Finding the Fourth Proportional to 501.18, 691.38 and 312.09

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Solution

The fourth proportional to 501.18, 691.38 and 312.09 is: 430.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.18 : 691.38 = 312.09 : x
  2. Step 2: Convert to fraction form
    501.18/691.38 = 312.09/x
  3. Step 3: Cross multiply
    501.18x = 691.38 × 312.09
  4. Step 4: Simplify right side
    501.18x = 215,772.78
  5. Step 5: Solve for x
    x = 215,772.78/501.18
  6. Step 6: Final answer
    x = 430.53

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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.