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Finding the Fourth Proportional to 409.60, 619.20 and 409.60

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Solution

The fourth proportional to 409.60, 619.20 and 409.60 is: 619.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.60 : 619.20 = 409.60 : x
  2. Step 2: Convert to fraction form
    409.60/619.20 = 409.60/x
  3. Step 3: Cross multiply
    409.60x = 619.20 × 409.60
  4. Step 4: Simplify right side
    409.60x = 253,624.32
  5. Step 5: Solve for x
    x = 253,624.32/409.60
  6. Step 6: Final answer
    x = 619.20

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.