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Finding the Fourth Proportional to 419.90, 629.58 and 386.96

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Solution

The fourth proportional to 419.90, 629.58 and 386.96 is: 580.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.90 : 629.58 = 386.96 : x
  2. Step 2: Convert to fraction form
    419.90/629.58 = 386.96/x
  3. Step 3: Cross multiply
    419.90x = 629.58 × 386.96
  4. Step 4: Simplify right side
    419.90x = 243,622.28
  5. Step 5: Solve for x
    x = 243,622.28/419.90
  6. Step 6: Final answer
    x = 580.19

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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.