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Finding the Fourth Proportional to 691.07, 1,030.79 and 628.79

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Solution

The fourth proportional to 691.07, 1,030.79 and 628.79 is: 937.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    691.07 : 1,030.79 = 628.79 : x
  2. Step 2: Convert to fraction form
    691.07/1,030.79 = 628.79/x
  3. Step 3: Cross multiply
    691.07x = 1,030.79 × 628.79
  4. Step 4: Simplify right side
    691.07x = 648,145.29
  5. Step 5: Solve for x
    x = 648,145.29/691.07
  6. Step 6: Final answer
    x = 937.89

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.