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Finding the Fourth Proportional to 619.34, 855.09 and 479.21

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Solution

The fourth proportional to 619.34, 855.09 and 479.21 is: 661.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.34 : 855.09 = 479.21 : x
  2. Step 2: Convert to fraction form
    619.34/855.09 = 479.21/x
  3. Step 3: Cross multiply
    619.34x = 855.09 × 479.21
  4. Step 4: Simplify right side
    619.34x = 409,763.40
  5. Step 5: Solve for x
    x = 409,763.40/619.34
  6. Step 6: Final answer
    x = 661.62

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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.