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Finding the Fourth Proportional to 620.39, 856.29 and 358.56

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Solution

The fourth proportional to 620.39, 856.29 and 358.56 is: 494.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.39 : 856.29 = 358.56 : x
  2. Step 2: Convert to fraction form
    620.39/856.29 = 358.56/x
  3. Step 3: Cross multiply
    620.39x = 856.29 × 358.56
  4. Step 4: Simplify right side
    620.39x = 307,031.34
  5. Step 5: Solve for x
    x = 307,031.34/620.39
  6. Step 6: Final answer
    x = 494.90

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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.