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Finding the Fourth Proportional to 419.63, 628.90 and 309.43

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Solution

The fourth proportional to 419.63, 628.90 and 309.43 is: 463.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.63 : 628.90 = 309.43 : x
  2. Step 2: Convert to fraction form
    419.63/628.90 = 309.43/x
  3. Step 3: Cross multiply
    419.63x = 628.90 × 309.43
  4. Step 4: Simplify right side
    419.63x = 194,600.53
  5. Step 5: Solve for x
    x = 194,600.53/419.63
  6. Step 6: Final answer
    x = 463.74

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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.