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Finding the Fourth Proportional to 459.75, 689.07 and 215.80

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Solution

The fourth proportional to 459.75, 689.07 and 215.80 is: 323.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    459.75 : 689.07 = 215.80 : x
  2. Step 2: Convert to fraction form
    459.75/689.07 = 215.80/x
  3. Step 3: Cross multiply
    459.75x = 689.07 × 215.80
  4. Step 4: Simplify right side
    459.75x = 148,701.31
  5. Step 5: Solve for x
    x = 148,701.31/459.75
  6. Step 6: Final answer
    x = 323.44

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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.