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Finding the Fourth Proportional to 636.42, 955.17 and 389.91

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Solution

The fourth proportional to 636.42, 955.17 and 389.91 is: 585.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.42 : 955.17 = 389.91 : x
  2. Step 2: Convert to fraction form
    636.42/955.17 = 389.91/x
  3. Step 3: Cross multiply
    636.42x = 955.17 × 389.91
  4. Step 4: Simplify right side
    636.42x = 372,430.33
  5. Step 5: Solve for x
    x = 372,430.33/636.42
  6. Step 6: Final answer
    x = 585.20

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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.