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Finding the Fourth Proportional to 429.04, 642.90 and 391.10

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Solution

The fourth proportional to 429.04, 642.90 and 391.10 is: 586.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.04 : 642.90 = 391.10 : x
  2. Step 2: Convert to fraction form
    429.04/642.90 = 391.10/x
  3. Step 3: Cross multiply
    429.04x = 642.90 × 391.10
  4. Step 4: Simplify right side
    429.04x = 251,438.19
  5. Step 5: Solve for x
    x = 251,438.19/429.04
  6. Step 6: Final answer
    x = 586.05

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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.