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Finding the Fourth Proportional to 380.61, 570.20 and 209.25

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Solution

The fourth proportional to 380.61, 570.20 and 209.25 is: 313.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.61 : 570.20 = 209.25 : x
  2. Step 2: Convert to fraction form
    380.61/570.20 = 209.25/x
  3. Step 3: Cross multiply
    380.61x = 570.20 × 209.25
  4. Step 4: Simplify right side
    380.61x = 119,313.30
  5. Step 5: Solve for x
    x = 119,313.30/380.61
  6. Step 6: Final answer
    x = 313.48

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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.