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Finding the Fourth Proportional to 809.32, 1,117.40 and 679.20

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Solution

The fourth proportional to 809.32, 1,117.40 and 679.20 is: 937.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.32 : 1,117.40 = 679.20 : x
  2. Step 2: Convert to fraction form
    809.32/1,117.40 = 679.20/x
  3. Step 3: Cross multiply
    809.32x = 1,117.40 × 679.20
  4. Step 4: Simplify right side
    809.32x = 758,938.08
  5. Step 5: Solve for x
    x = 758,938.08/809.32
  6. Step 6: Final answer
    x = 937.75

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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.