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Finding the Fourth Proportional to 620.87, 856.73 and 355.34

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Solution

The fourth proportional to 620.87, 856.73 and 355.34 is: 490.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.87 : 856.73 = 355.34 : x
  2. Step 2: Convert to fraction form
    620.87/856.73 = 355.34/x
  3. Step 3: Cross multiply
    620.87x = 856.73 × 355.34
  4. Step 4: Simplify right side
    620.87x = 304,426.65
  5. Step 5: Solve for x
    x = 304,426.65/620.87
  6. Step 6: Final answer
    x = 490.33

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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.