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Finding the Fourth Proportional to 306.80, 423.61 and 208.52

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Solution

The fourth proportional to 306.80, 423.61 and 208.52 is: 287.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.80 : 423.61 = 208.52 : x
  2. Step 2: Convert to fraction form
    306.80/423.61 = 208.52/x
  3. Step 3: Cross multiply
    306.80x = 423.61 × 208.52
  4. Step 4: Simplify right side
    306.80x = 88,331.16
  5. Step 5: Solve for x
    x = 88,331.16/306.80
  6. Step 6: Final answer
    x = 287.91

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.