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Finding the Fourth Proportional to 429.50, 647.60 and 389.41

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Solution

The fourth proportional to 429.50, 647.60 and 389.41 is: 587.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.50 : 647.60 = 389.41 : x
  2. Step 2: Convert to fraction form
    429.50/647.60 = 389.41/x
  3. Step 3: Cross multiply
    429.50x = 647.60 × 389.41
  4. Step 4: Simplify right side
    429.50x = 252,178.35
  5. Step 5: Solve for x
    x = 252,178.35/429.50
  6. Step 6: Final answer
    x = 587.14

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.