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Finding the Fourth Proportional to 459.90, 690.35 and 408.87

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Solution

The fourth proportional to 459.90, 690.35 and 408.87 is: 613.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    459.90 : 690.35 = 408.87 : x
  2. Step 2: Convert to fraction form
    459.90/690.35 = 408.87/x
  3. Step 3: Cross multiply
    459.90x = 690.35 × 408.87
  4. Step 4: Simplify right side
    459.90x = 282,261.36
  5. Step 5: Solve for x
    x = 282,261.36/459.90
  6. Step 6: Final answer
    x = 613.75

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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.