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Finding the Fourth Proportional to 306.80, 459.12 and 209.31

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Solution

The fourth proportional to 306.80, 459.12 and 209.31 is: 313.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.80 : 459.12 = 209.31 : x
  2. Step 2: Convert to fraction form
    306.80/459.12 = 209.31/x
  3. Step 3: Cross multiply
    306.80x = 459.12 × 209.31
  4. Step 4: Simplify right side
    306.80x = 96,098.41
  5. Step 5: Solve for x
    x = 96,098.41/306.80
  6. Step 6: Final answer
    x = 313.23

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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.