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Finding the Fourth Proportional to 630.88, 870.95 and 490.68

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Solution

The fourth proportional to 630.88, 870.95 and 490.68 is: 677.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.88 : 870.95 = 490.68 : x
  2. Step 2: Convert to fraction form
    630.88/870.95 = 490.68/x
  3. Step 3: Cross multiply
    630.88x = 870.95 × 490.68
  4. Step 4: Simplify right side
    630.88x = 427,358.97
  5. Step 5: Solve for x
    x = 427,358.97/630.88
  6. Step 6: Final answer
    x = 677.40

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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.