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Finding the Fourth Proportional to 620.82, 856.85 and 355.32

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Solution

The fourth proportional to 620.82, 856.85 and 355.32 is: 490.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.82 : 856.85 = 355.32 : x
  2. Step 2: Convert to fraction form
    620.82/856.85 = 355.32/x
  3. Step 3: Cross multiply
    620.82x = 856.85 × 355.32
  4. Step 4: Simplify right side
    620.82x = 304,454.17
  5. Step 5: Solve for x
    x = 304,454.17/620.82
  6. Step 6: Final answer
    x = 490.41

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1.5x scale

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.