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Finding the Fourth Proportional to 420.30, 588.90 and 420.30

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Solution

The fourth proportional to 420.30, 588.90 and 420.30 is: 588.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.30 : 588.90 = 420.30 : x
  2. Step 2: Convert to fraction form
    420.30/588.90 = 420.30/x
  3. Step 3: Cross multiply
    420.30x = 588.90 × 420.30
  4. Step 4: Simplify right side
    420.30x = 247,514.67
  5. Step 5: Solve for x
    x = 247,514.67/420.30
  6. Step 6: Final answer
    x = 588.90

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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.