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Finding the Fourth Proportional to 621.45, 857.47 and 372.79

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Solution

The fourth proportional to 621.45, 857.47 and 372.79 is: 514.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.45 : 857.47 = 372.79 : x
  2. Step 2: Convert to fraction form
    621.45/857.47 = 372.79/x
  3. Step 3: Cross multiply
    621.45x = 857.47 × 372.79
  4. Step 4: Simplify right side
    621.45x = 319,656.24
  5. Step 5: Solve for x
    x = 319,656.24/621.45
  6. Step 6: Final answer
    x = 514.37

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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.