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Finding the Fourth Proportional to 306.85, 423.19 and 279.17

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Solution

The fourth proportional to 306.85, 423.19 and 279.17 is: 385.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.85 : 423.19 = 279.17 : x
  2. Step 2: Convert to fraction form
    306.85/423.19 = 279.17/x
  3. Step 3: Cross multiply
    306.85x = 423.19 × 279.17
  4. Step 4: Simplify right side
    306.85x = 118,141.95
  5. Step 5: Solve for x
    x = 118,141.95/306.85
  6. Step 6: Final answer
    x = 385.02

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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.