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Finding the Fourth Proportional to 665.64, 991.08 and 662.40

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Solution

The fourth proportional to 665.64, 991.08 and 662.40 is: 986.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.64 : 991.08 = 662.40 : x
  2. Step 2: Convert to fraction form
    665.64/991.08 = 662.40/x
  3. Step 3: Cross multiply
    665.64x = 991.08 × 662.40
  4. Step 4: Simplify right side
    665.64x = 656,491.39
  5. Step 5: Solve for x
    x = 656,491.39/665.64
  6. Step 6: Final answer
    x = 986.26

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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.