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Finding the Fourth Proportional to 689.51, 951.57 and 394.79

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Solution

The fourth proportional to 689.51, 951.57 and 394.79 is: 544.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.51 : 951.57 = 394.79 : x
  2. Step 2: Convert to fraction form
    689.51/951.57 = 394.79/x
  3. Step 3: Cross multiply
    689.51x = 951.57 × 394.79
  4. Step 4: Simplify right side
    689.51x = 375,667.94
  5. Step 5: Solve for x
    x = 375,667.94/689.51
  6. Step 6: Final answer
    x = 544.84

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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.