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Finding the Fourth Proportional to 642.28, 955.73 and 640.12

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Solution

The fourth proportional to 642.28, 955.73 and 640.12 is: 952.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.28 : 955.73 = 640.12 : x
  2. Step 2: Convert to fraction form
    642.28/955.73 = 640.12/x
  3. Step 3: Cross multiply
    642.28x = 955.73 × 640.12
  4. Step 4: Simplify right side
    642.28x = 611,781.89
  5. Step 5: Solve for x
    x = 611,781.89/642.28
  6. Step 6: Final answer
    x = 952.52

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.