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Finding the Fourth Proportional to 620.56, 856.38 and 340.80

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Solution

The fourth proportional to 620.56, 856.38 and 340.80 is: 470.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.56 : 856.38 = 340.80 : x
  2. Step 2: Convert to fraction form
    620.56/856.38 = 340.80/x
  3. Step 3: Cross multiply
    620.56x = 856.38 × 340.80
  4. Step 4: Simplify right side
    620.56x = 291,854.30
  5. Step 5: Solve for x
    x = 291,854.30/620.56
  6. Step 6: Final answer
    x = 470.31

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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.