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Finding the Fourth Proportional to 421.35, 580.80 and 347.55

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Solution

The fourth proportional to 421.35, 580.80 and 347.55 is: 479.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.35 : 580.80 = 347.55 : x
  2. Step 2: Convert to fraction form
    421.35/580.80 = 347.55/x
  3. Step 3: Cross multiply
    421.35x = 580.80 × 347.55
  4. Step 4: Simplify right side
    421.35x = 201,857.04
  5. Step 5: Solve for x
    x = 201,857.04/421.35
  6. Step 6: Final answer
    x = 479.07

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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.