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Finding the Fourth Proportional to 809.20, 1,211.28 and 443.08

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Solution

The fourth proportional to 809.20, 1,211.28 and 443.08 is: 663.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.20 : 1,211.28 = 443.08 : x
  2. Step 2: Convert to fraction form
    809.20/1,211.28 = 443.08/x
  3. Step 3: Cross multiply
    809.20x = 1,211.28 × 443.08
  4. Step 4: Simplify right side
    809.20x = 536,693.94
  5. Step 5: Solve for x
    x = 536,693.94/809.20
  6. Step 6: Final answer
    x = 663.24

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.