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Finding the Fourth Proportional to 687.70, 949.14 and 407.92

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Solution

The fourth proportional to 687.70, 949.14 and 407.92 is: 563.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.70 : 949.14 = 407.92 : x
  2. Step 2: Convert to fraction form
    687.70/949.14 = 407.92/x
  3. Step 3: Cross multiply
    687.70x = 949.14 × 407.92
  4. Step 4: Simplify right side
    687.70x = 387,173.19
  5. Step 5: Solve for x
    x = 387,173.19/687.70
  6. Step 6: Final answer
    x = 563.00

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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.