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Finding the Fourth Proportional to 620.81, 856.65 and 358.91

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Solution

The fourth proportional to 620.81, 856.65 and 358.91 is: 495.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.81 : 856.65 = 358.91 : x
  2. Step 2: Convert to fraction form
    620.81/856.65 = 358.91/x
  3. Step 3: Cross multiply
    620.81x = 856.65 × 358.91
  4. Step 4: Simplify right side
    620.81x = 307,460.25
  5. Step 5: Solve for x
    x = 307,460.25/620.81
  6. Step 6: Final answer
    x = 495.26

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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.