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Finding the Fourth Proportional to 422.12, 631.80 and 291.80

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Solution

The fourth proportional to 422.12, 631.80 and 291.80 is: 436.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    422.12 : 631.80 = 291.80 : x
  2. Step 2: Convert to fraction form
    422.12/631.80 = 291.80/x
  3. Step 3: Cross multiply
    422.12x = 631.80 × 291.80
  4. Step 4: Simplify right side
    422.12x = 184,359.24
  5. Step 5: Solve for x
    x = 184,359.24/422.12
  6. Step 6: Final answer
    x = 436.75

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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.