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Finding the Fourth Proportional to 528.20, 788.42 and 490.17

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Solution

The fourth proportional to 528.20, 788.42 and 490.17 is: 731.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.20 : 788.42 = 490.17 : x
  2. Step 2: Convert to fraction form
    528.20/788.42 = 490.17/x
  3. Step 3: Cross multiply
    528.20x = 788.42 × 490.17
  4. Step 4: Simplify right side
    528.20x = 386,459.83
  5. Step 5: Solve for x
    x = 386,459.83/528.20
  6. Step 6: Final answer
    x = 731.65

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.