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Finding the Fourth Proportional to 306.40, 422.40 and 279.04

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Solution

The fourth proportional to 306.40, 422.40 and 279.04 is: 384.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.40 : 422.40 = 279.04 : x
  2. Step 2: Convert to fraction form
    306.40/422.40 = 279.04/x
  3. Step 3: Cross multiply
    306.40x = 422.40 × 279.04
  4. Step 4: Simplify right side
    306.40x = 117,866.50
  5. Step 5: Solve for x
    x = 117,866.50/306.40
  6. Step 6: Final answer
    x = 384.68

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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.