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Finding the Fourth Proportional to 648, 976.86 and 638.28

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Solution

The fourth proportional to 648, 976.86 and 638.28 is: 962.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    648 : 976.86 = 638.28 : x
  2. Step 2: Convert to fraction form
    648/976.86 = 638.28/x
  3. Step 3: Cross multiply
    648x = 976.86 × 638.28
  4. Step 4: Simplify right side
    648x = 623,510.20
  5. Step 5: Solve for x
    x = 623,510.20/648
  6. Step 6: Final answer
    x = 962.21

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.