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Finding the Fourth Proportional to 619.56, 929.10 and 415.20

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Solution

The fourth proportional to 619.56, 929.10 and 415.20 is: 622.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.56 : 929.10 = 415.20 : x
  2. Step 2: Convert to fraction form
    619.56/929.10 = 415.20/x
  3. Step 3: Cross multiply
    619.56x = 929.10 × 415.20
  4. Step 4: Simplify right side
    619.56x = 385,762.32
  5. Step 5: Solve for x
    x = 385,762.32/619.56
  6. Step 6: Final answer
    x = 622.64

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.