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Finding the Fourth Proportional to 621.24, 856.98 and 387.96

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Solution

The fourth proportional to 621.24, 856.98 and 387.96 is: 535.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.24 : 856.98 = 387.96 : x
  2. Step 2: Convert to fraction form
    621.24/856.98 = 387.96/x
  3. Step 3: Cross multiply
    621.24x = 856.98 × 387.96
  4. Step 4: Simplify right side
    621.24x = 332,473.96
  5. Step 5: Solve for x
    x = 332,473.96/621.24
  6. Step 6: Final answer
    x = 535.18

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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.