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Finding the Fourth Proportional to 419.72, 629.61 and 172.87

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Solution

The fourth proportional to 419.72, 629.61 and 172.87 is: 259.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.72 : 629.61 = 172.87 : x
  2. Step 2: Convert to fraction form
    419.72/629.61 = 172.87/x
  3. Step 3: Cross multiply
    419.72x = 629.61 × 172.87
  4. Step 4: Simplify right side
    419.72x = 108,838.46
  5. Step 5: Solve for x
    x = 108,838.46/419.72
  6. Step 6: Final answer
    x = 259.32

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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.