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Finding the Fourth Proportional to 689.51, 951.54 and 394.81

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Solution

The fourth proportional to 689.51, 951.54 and 394.81 is: 544.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.51 : 951.54 = 394.81 : x
  2. Step 2: Convert to fraction form
    689.51/951.54 = 394.81/x
  3. Step 3: Cross multiply
    689.51x = 951.54 × 394.81
  4. Step 4: Simplify right side
    689.51x = 375,677.51
  5. Step 5: Solve for x
    x = 375,677.51/689.51
  6. Step 6: Final answer
    x = 544.85

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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.