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Finding the Fourth Proportional to 642.92, 887.56 and 407.12

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Solution

The fourth proportional to 642.92, 887.56 and 407.12 is: 562.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.92 : 887.56 = 407.12 : x
  2. Step 2: Convert to fraction form
    642.92/887.56 = 407.12/x
  3. Step 3: Cross multiply
    642.92x = 887.56 × 407.12
  4. Step 4: Simplify right side
    642.92x = 361,339.69
  5. Step 5: Solve for x
    x = 361,339.69/642.92
  6. Step 6: Final answer
    x = 562.03

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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.