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Finding the Fourth Proportional to 428.13, 590.61 and 288.21

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Solution

The fourth proportional to 428.13, 590.61 and 288.21 is: 397.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.13 : 590.61 = 288.21 : x
  2. Step 2: Convert to fraction form
    428.13/590.61 = 288.21/x
  3. Step 3: Cross multiply
    428.13x = 590.61 × 288.21
  4. Step 4: Simplify right side
    428.13x = 170,219.71
  5. Step 5: Solve for x
    x = 170,219.71/428.13
  6. Step 6: Final answer
    x = 397.59

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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.