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Finding the Fourth Proportional to 285.80, 429.15 and 209.30

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Solution

The fourth proportional to 285.80, 429.15 and 209.30 is: 314.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.80 : 429.15 = 209.30 : x
  2. Step 2: Convert to fraction form
    285.80/429.15 = 209.30/x
  3. Step 3: Cross multiply
    285.80x = 429.15 × 209.30
  4. Step 4: Simplify right side
    285.80x = 89,821.10
  5. Step 5: Solve for x
    x = 89,821.10/285.80
  6. Step 6: Final answer
    x = 314.28

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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.