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Finding the Fourth Proportional to 687.79, 948.92 and 407.94

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Solution

The fourth proportional to 687.79, 948.92 and 407.94 is: 562.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.79 : 948.92 = 407.94 : x
  2. Step 2: Convert to fraction form
    687.79/948.92 = 407.94/x
  3. Step 3: Cross multiply
    687.79x = 948.92 × 407.94
  4. Step 4: Simplify right side
    687.79x = 387,096.83
  5. Step 5: Solve for x
    x = 387,096.83/687.79
  6. Step 6: Final answer
    x = 562.81

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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.