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Finding the Fourth Proportional to 620.17, 855.85 and 340.40

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Solution

The fourth proportional to 620.17, 855.85 and 340.40 is: 469.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.17 : 855.85 = 340.40 : x
  2. Step 2: Convert to fraction form
    620.17/855.85 = 340.40/x
  3. Step 3: Cross multiply
    620.17x = 855.85 × 340.40
  4. Step 4: Simplify right side
    620.17x = 291,329.64
  5. Step 5: Solve for x
    x = 291,329.64/620.17
  6. Step 6: Final answer
    x = 469.76

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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.