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Finding the Fourth Proportional to 687.89, 948.95 and 408.00

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Solution

The fourth proportional to 687.89, 948.95 and 408.00 is: 562.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.89 : 948.95 = 408.00 : x
  2. Step 2: Convert to fraction form
    687.89/948.95 = 408.00/x
  3. Step 3: Cross multiply
    687.89x = 948.95 × 408.00
  4. Step 4: Simplify right side
    687.89x = 387,174.65
  5. Step 5: Solve for x
    x = 387,174.65/687.89
  6. Step 6: Final answer
    x = 562.84

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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.