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Finding the Fourth Proportional to 659.11, 988.16 and 399.05

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Solution

The fourth proportional to 659.11, 988.16 and 399.05 is: 598.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.11 : 988.16 = 399.05 : x
  2. Step 2: Convert to fraction form
    659.11/988.16 = 399.05/x
  3. Step 3: Cross multiply
    659.11x = 988.16 × 399.05
  4. Step 4: Simplify right side
    659.11x = 394,318.31
  5. Step 5: Solve for x
    x = 394,318.31/659.11
  6. Step 6: Final answer
    x = 598.26

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.