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Finding the Fourth Proportional to 636.80, 955.17 and 389.99

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Solution

The fourth proportional to 636.80, 955.17 and 389.99 is: 584.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.80 : 955.17 = 389.99 : x
  2. Step 2: Convert to fraction form
    636.80/955.17 = 389.99/x
  3. Step 3: Cross multiply
    636.80x = 955.17 × 389.99
  4. Step 4: Simplify right side
    636.80x = 372,509.14
  5. Step 5: Solve for x
    x = 372,509.14/636.80
  6. Step 6: Final answer
    x = 584.97

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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.