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Finding the Fourth Proportional to 438.20, 656.80 and 329.64

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Solution

The fourth proportional to 438.20, 656.80 and 329.64 is: 494.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.20 : 656.80 = 329.64 : x
  2. Step 2: Convert to fraction form
    438.20/656.80 = 329.64/x
  3. Step 3: Cross multiply
    438.20x = 656.80 × 329.64
  4. Step 4: Simplify right side
    438.20x = 216,507.55
  5. Step 5: Solve for x
    x = 216,507.55/438.20
  6. Step 6: Final answer
    x = 494.08

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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.