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Finding the Fourth Proportional to 500.85, 690.48 and 389.88

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Solution

The fourth proportional to 500.85, 690.48 and 389.88 is: 537.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.85 : 690.48 = 389.88 : x
  2. Step 2: Convert to fraction form
    500.85/690.48 = 389.88/x
  3. Step 3: Cross multiply
    500.85x = 690.48 × 389.88
  4. Step 4: Simplify right side
    500.85x = 269,204.34
  5. Step 5: Solve for x
    x = 269,204.34/500.85
  6. Step 6: Final answer
    x = 537.49

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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.