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Finding the Fourth Proportional to 638.85, 881.55 and 359.01

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Solution

The fourth proportional to 638.85, 881.55 and 359.01 is: 495.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.85 : 881.55 = 359.01 : x
  2. Step 2: Convert to fraction form
    638.85/881.55 = 359.01/x
  3. Step 3: Cross multiply
    638.85x = 881.55 × 359.01
  4. Step 4: Simplify right side
    638.85x = 316,485.27
  5. Step 5: Solve for x
    x = 316,485.27/638.85
  6. Step 6: Final answer
    x = 495.40

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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.