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Finding the Fourth Proportional to 687.75, 949.10 and 389.01

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Solution

The fourth proportional to 687.75, 949.10 and 389.01 is: 536.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.75 : 949.10 = 389.01 : x
  2. Step 2: Convert to fraction form
    687.75/949.10 = 389.01/x
  3. Step 3: Cross multiply
    687.75x = 949.10 × 389.01
  4. Step 4: Simplify right side
    687.75x = 369,204.65
  5. Step 5: Solve for x
    x = 369,204.65/687.75
  6. Step 6: Final answer
    x = 536.83

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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.