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Finding the Fourth Proportional to 621.38, 857.62 and 355.84

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Solution

The fourth proportional to 621.38, 857.62 and 355.84 is: 491.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.38 : 857.62 = 355.84 : x
  2. Step 2: Convert to fraction form
    621.38/857.62 = 355.84/x
  3. Step 3: Cross multiply
    621.38x = 857.62 × 355.84
  4. Step 4: Simplify right side
    621.38x = 305,172.47
  5. Step 5: Solve for x
    x = 305,172.47/621.38
  6. Step 6: Final answer
    x = 491.12

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.