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Finding the Fourth Proportional to 420.39, 629.64 and 410.07

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Solution

The fourth proportional to 420.39, 629.64 and 410.07 is: 614.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.39 : 629.64 = 410.07 : x
  2. Step 2: Convert to fraction form
    420.39/629.64 = 410.07/x
  3. Step 3: Cross multiply
    420.39x = 629.64 × 410.07
  4. Step 4: Simplify right side
    420.39x = 258,196.47
  5. Step 5: Solve for x
    x = 258,196.47/420.39
  6. Step 6: Final answer
    x = 614.18

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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.