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Finding the Fourth Proportional to 689.38, 951.31 and 394.58

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Solution

The fourth proportional to 689.38, 951.31 and 394.58 is: 544.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.38 : 951.31 = 394.58 : x
  2. Step 2: Convert to fraction form
    689.38/951.31 = 394.58/x
  3. Step 3: Cross multiply
    689.38x = 951.31 × 394.58
  4. Step 4: Simplify right side
    689.38x = 375,367.90
  5. Step 5: Solve for x
    x = 375,367.90/689.38
  6. Step 6: Final answer
    x = 544.50

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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.