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Finding the Fourth Proportional to 500.45, 690.63 and 279.42

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Solution

The fourth proportional to 500.45, 690.63 and 279.42 is: 385.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.45 : 690.63 = 279.42 : x
  2. Step 2: Convert to fraction form
    500.45/690.63 = 279.42/x
  3. Step 3: Cross multiply
    500.45x = 690.63 × 279.42
  4. Step 4: Simplify right side
    500.45x = 192,972.20
  5. Step 5: Solve for x
    x = 192,972.20/500.45
  6. Step 6: Final answer
    x = 385.60

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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.