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Finding the Fourth Proportional to 635.70, 877.17 and 399.78

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Solution

The fourth proportional to 635.70, 877.17 and 399.78 is: 551.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    635.70 : 877.17 = 399.78 : x
  2. Step 2: Convert to fraction form
    635.70/877.17 = 399.78/x
  3. Step 3: Cross multiply
    635.70x = 877.17 × 399.78
  4. Step 4: Simplify right side
    635.70x = 350,675.02
  5. Step 5: Solve for x
    x = 350,675.02/635.70
  6. Step 6: Final answer
    x = 551.64

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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.