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Finding the Fourth Proportional to 665.55, 998.33 and 640.35

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Solution

The fourth proportional to 665.55, 998.33 and 640.35 is: 960.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.55 : 998.33 = 640.35 : x
  2. Step 2: Convert to fraction form
    665.55/998.33 = 640.35/x
  3. Step 3: Cross multiply
    665.55x = 998.33 × 640.35
  4. Step 4: Simplify right side
    665.55x = 639,277.41
  5. Step 5: Solve for x
    x = 639,277.41/665.55
  6. Step 6: Final answer
    x = 960.53

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.