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Finding the Fourth Proportional to 666.35, 919.57 and 470.21

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Solution

The fourth proportional to 666.35, 919.57 and 470.21 is: 648.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.35 : 919.57 = 470.21 : x
  2. Step 2: Convert to fraction form
    666.35/919.57 = 470.21/x
  3. Step 3: Cross multiply
    666.35x = 919.57 × 470.21
  4. Step 4: Simplify right side
    666.35x = 432,384.13
  5. Step 5: Solve for x
    x = 432,384.13/666.35
  6. Step 6: Final answer
    x = 648.88

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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.