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Finding the Fourth Proportional to 620.47, 856.26 and 340.72

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Solution

The fourth proportional to 620.47, 856.26 and 340.72 is: 470.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.47 : 856.26 = 340.72 : x
  2. Step 2: Convert to fraction form
    620.47/856.26 = 340.72/x
  3. Step 3: Cross multiply
    620.47x = 856.26 × 340.72
  4. Step 4: Simplify right side
    620.47x = 291,740.78
  5. Step 5: Solve for x
    x = 291,740.78/620.47
  6. Step 6: Final answer
    x = 470.19

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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.