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Finding the Fourth Proportional to 666.03, 993.35 and 642.81

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Solution

The fourth proportional to 666.03, 993.35 and 642.81 is: 958.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.03 : 993.35 = 642.81 : x
  2. Step 2: Convert to fraction form
    666.03/993.35 = 642.81/x
  3. Step 3: Cross multiply
    666.03x = 993.35 × 642.81
  4. Step 4: Simplify right side
    666.03x = 638,535.31
  5. Step 5: Solve for x
    x = 638,535.31/666.03
  6. Step 6: Final answer
    x = 958.72

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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.