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Finding the Fourth Proportional to 809.32, 1,117.78 and 645.32

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Solution

The fourth proportional to 809.32, 1,117.78 and 645.32 is: 891.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.32 : 1,117.78 = 645.32 : x
  2. Step 2: Convert to fraction form
    809.32/1,117.78 = 645.32/x
  3. Step 3: Cross multiply
    809.32x = 1,117.78 × 645.32
  4. Step 4: Simplify right side
    809.32x = 721,325.79
  5. Step 5: Solve for x
    x = 721,325.79/809.32
  6. Step 6: Final answer
    x = 891.27

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Half scale
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Double scale
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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.