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Finding the Fourth Proportional to 428.09, 590.49 and 345.20

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Solution

The fourth proportional to 428.09, 590.49 and 345.20 is: 476.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.09 : 590.49 = 345.20 : x
  2. Step 2: Convert to fraction form
    428.09/590.49 = 345.20/x
  3. Step 3: Cross multiply
    428.09x = 590.49 × 345.20
  4. Step 4: Simplify right side
    428.09x = 203,834.20
  5. Step 5: Solve for x
    x = 203,834.20/428.09
  6. Step 6: Final answer
    x = 476.15

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.