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Finding the Fourth Proportional to 640.55, 884.01 and 392.02

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Solution

The fourth proportional to 640.55, 884.01 and 392.02 is: 541.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.55 : 884.01 = 392.02 : x
  2. Step 2: Convert to fraction form
    640.55/884.01 = 392.02/x
  3. Step 3: Cross multiply
    640.55x = 884.01 × 392.02
  4. Step 4: Simplify right side
    640.55x = 346,551.63
  5. Step 5: Solve for x
    x = 346,551.63/640.55
  6. Step 6: Final answer
    x = 541.02

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.