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Finding the Fourth Proportional to 306.99, 423.83 and 208.78

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Solution

The fourth proportional to 306.99, 423.83 and 208.78 is: 288.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.99 : 423.83 = 208.78 : x
  2. Step 2: Convert to fraction form
    306.99/423.83 = 208.78/x
  3. Step 3: Cross multiply
    306.99x = 423.83 × 208.78
  4. Step 4: Simplify right side
    306.99x = 88,486.69
  5. Step 5: Solve for x
    x = 88,486.69/306.99
  6. Step 6: Final answer
    x = 288.24

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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.