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Finding the Fourth Proportional to 306, 422.30 and 239.70

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Solution

The fourth proportional to 306, 422.30 and 239.70 is: 330.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    306 : 422.30 = 239.70 : x
  2. Step 2: Convert to fraction form
    306/422.30 = 239.70/x
  3. Step 3: Cross multiply
    306x = 422.30 × 239.70
  4. Step 4: Simplify right side
    306x = 101,224.11
  5. Step 5: Solve for x
    x = 101,224.11/306
  6. Step 6: Final answer
    x = 330.80

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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.