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Finding the Fourth Proportional to 642.40, 887.52 and 545.28

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Solution

The fourth proportional to 642.40, 887.52 and 545.28 is: 753.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.40 : 887.52 = 545.28 : x
  2. Step 2: Convert to fraction form
    642.40/887.52 = 545.28/x
  3. Step 3: Cross multiply
    642.40x = 887.52 × 545.28
  4. Step 4: Simplify right side
    642.40x = 483,946.91
  5. Step 5: Solve for x
    x = 483,946.91/642.40
  6. Step 6: Final answer
    x = 753.34

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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.