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Finding the Fourth Proportional to 428.28, 590.79 and 288.15

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Solution

The fourth proportional to 428.28, 590.79 and 288.15 is: 397.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.28 : 590.79 = 288.15 : x
  2. Step 2: Convert to fraction form
    428.28/590.79 = 288.15/x
  3. Step 3: Cross multiply
    428.28x = 590.79 × 288.15
  4. Step 4: Simplify right side
    428.28x = 170,236.14
  5. Step 5: Solve for x
    x = 170,236.14/428.28
  6. Step 6: Final answer
    x = 397.49

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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.