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Finding the Fourth Proportional to 639.88, 883.23 and 400.74

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Solution

The fourth proportional to 639.88, 883.23 and 400.74 is: 553.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.88 : 883.23 = 400.74 : x
  2. Step 2: Convert to fraction form
    639.88/883.23 = 400.74/x
  3. Step 3: Cross multiply
    639.88x = 883.23 × 400.74
  4. Step 4: Simplify right side
    639.88x = 353,941.17
  5. Step 5: Solve for x
    x = 353,941.17/639.88
  6. Step 6: Final answer
    x = 553.14

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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.