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Finding the Fourth Proportional to 687.02, 1,023.39 and 649.76

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Solution

The fourth proportional to 687.02, 1,023.39 and 649.76 is: 967.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.02 : 1,023.39 = 649.76 : x
  2. Step 2: Convert to fraction form
    687.02/1,023.39 = 649.76/x
  3. Step 3: Cross multiply
    687.02x = 1,023.39 × 649.76
  4. Step 4: Simplify right side
    687.02x = 664,957.89
  5. Step 5: Solve for x
    x = 664,957.89/687.02
  6. Step 6: Final answer
    x = 967.89

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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.