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Finding the Fourth Proportional to 689.79, 951.72 and 395.07

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Solution

The fourth proportional to 689.79, 951.72 and 395.07 is: 545.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.79 : 951.72 = 395.07 : x
  2. Step 2: Convert to fraction form
    689.79/951.72 = 395.07/x
  3. Step 3: Cross multiply
    689.79x = 951.72 × 395.07
  4. Step 4: Simplify right side
    689.79x = 375,996.02
  5. Step 5: Solve for x
    x = 375,996.02/689.79
  6. Step 6: Final answer
    x = 545.09

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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.