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Finding the Fourth Proportional to 459.40, 689.09 and 215.75

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Solution

The fourth proportional to 459.40, 689.09 and 215.75 is: 323.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    459.40 : 689.09 = 215.75 : x
  2. Step 2: Convert to fraction form
    459.40/689.09 = 215.75/x
  3. Step 3: Cross multiply
    459.40x = 689.09 × 215.75
  4. Step 4: Simplify right side
    459.40x = 148,668.37
  5. Step 5: Solve for x
    x = 148,668.37/459.40
  6. Step 6: Final answer
    x = 323.62

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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.