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Finding the Fourth Proportional to 662.76, 989.13 and 645.48

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Solution

The fourth proportional to 662.76, 989.13 and 645.48 is: 963.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    662.76 : 989.13 = 645.48 : x
  2. Step 2: Convert to fraction form
    662.76/989.13 = 645.48/x
  3. Step 3: Cross multiply
    662.76x = 989.13 × 645.48
  4. Step 4: Simplify right side
    662.76x = 638,463.63
  5. Step 5: Solve for x
    x = 638,463.63/662.76
  6. Step 6: Final answer
    x = 963.34

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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.