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Finding the Fourth Proportional to 638.08, 880.26 and 389.20

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Solution

The fourth proportional to 638.08, 880.26 and 389.20 is: 536.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.08 : 880.26 = 389.20 : x
  2. Step 2: Convert to fraction form
    638.08/880.26 = 389.20/x
  3. Step 3: Cross multiply
    638.08x = 880.26 × 389.20
  4. Step 4: Simplify right side
    638.08x = 342,597.19
  5. Step 5: Solve for x
    x = 342,597.19/638.08
  6. Step 6: Final answer
    x = 536.92

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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.