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Finding the Fourth Proportional to 420.25, 629.22 and 317.22

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Solution

The fourth proportional to 420.25, 629.22 and 317.22 is: 474.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.25 : 629.22 = 317.22 : x
  2. Step 2: Convert to fraction form
    420.25/629.22 = 317.22/x
  3. Step 3: Cross multiply
    420.25x = 629.22 × 317.22
  4. Step 4: Simplify right side
    420.25x = 199,601.17
  5. Step 5: Solve for x
    x = 199,601.17/420.25
  6. Step 6: Final answer
    x = 474.96

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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.