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Finding the Fourth Proportional to 500.34, 690.45 and 279.30

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Solution

The fourth proportional to 500.34, 690.45 and 279.30 is: 385.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.34 : 690.45 = 279.30 : x
  2. Step 2: Convert to fraction form
    500.34/690.45 = 279.30/x
  3. Step 3: Cross multiply
    500.34x = 690.45 × 279.30
  4. Step 4: Simplify right side
    500.34x = 192,842.69
  5. Step 5: Solve for x
    x = 192,842.69/500.34
  6. Step 6: Final answer
    x = 385.42

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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.