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Finding the Fourth Proportional to 621.20, 857.28 and 372.63

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Solution

The fourth proportional to 621.20, 857.28 and 372.63 is: 514.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.20 : 857.28 = 372.63 : x
  2. Step 2: Convert to fraction form
    621.20/857.28 = 372.63/x
  3. Step 3: Cross multiply
    621.20x = 857.28 × 372.63
  4. Step 4: Simplify right side
    621.20x = 319,452.86
  5. Step 5: Solve for x
    x = 319,452.86/621.20
  6. Step 6: Final answer
    x = 514.25

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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.