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Finding the Fourth Proportional to 689.71, 951.80 and 394.98

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Solution

The fourth proportional to 689.71, 951.80 and 394.98 is: 545.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.71 : 951.80 = 394.98 : x
  2. Step 2: Convert to fraction form
    689.71/951.80 = 394.98/x
  3. Step 3: Cross multiply
    689.71x = 951.80 × 394.98
  4. Step 4: Simplify right side
    689.71x = 375,935.23
  5. Step 5: Solve for x
    x = 375,935.23/689.71
  6. Step 6: Final answer
    x = 545.07

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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.