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Finding the Fourth Proportional to 689.16, 950.80 and 394.21

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Solution

The fourth proportional to 689.16, 950.80 and 394.21 is: 543.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.16 : 950.80 = 394.21 : x
  2. Step 2: Convert to fraction form
    689.16/950.80 = 394.21/x
  3. Step 3: Cross multiply
    689.16x = 950.80 × 394.21
  4. Step 4: Simplify right side
    689.16x = 374,814.87
  5. Step 5: Solve for x
    x = 374,814.87/689.16
  6. Step 6: Final answer
    x = 543.87

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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.