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Finding the Fourth Proportional to 621.52, 857.10 and 388.60

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Solution

The fourth proportional to 621.52, 857.10 and 388.60 is: 535.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.52 : 857.10 = 388.60 : x
  2. Step 2: Convert to fraction form
    621.52/857.10 = 388.60/x
  3. Step 3: Cross multiply
    621.52x = 857.10 × 388.60
  4. Step 4: Simplify right side
    621.52x = 333,069.06
  5. Step 5: Solve for x
    x = 333,069.06/621.52
  6. Step 6: Final answer
    x = 535.89

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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.