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Finding the Fourth Proportional to 689.43, 951.39 and 394.72

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Solution

The fourth proportional to 689.43, 951.39 and 394.72 is: 544.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.43 : 951.39 = 394.72 : x
  2. Step 2: Convert to fraction form
    689.43/951.39 = 394.72/x
  3. Step 3: Cross multiply
    689.43x = 951.39 × 394.72
  4. Step 4: Simplify right side
    689.43x = 375,530.28
  5. Step 5: Solve for x
    x = 375,530.28/689.43
  6. Step 6: Final answer
    x = 544.70

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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.