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Finding the Fourth Proportional to 630.28, 870.06 and 490.78

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Solution

The fourth proportional to 630.28, 870.06 and 490.78 is: 677.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.28 : 870.06 = 490.78 : x
  2. Step 2: Convert to fraction form
    630.28/870.06 = 490.78/x
  3. Step 3: Cross multiply
    630.28x = 870.06 × 490.78
  4. Step 4: Simplify right side
    630.28x = 427,008.05
  5. Step 5: Solve for x
    x = 427,008.05/630.28
  6. Step 6: Final answer
    x = 677.49

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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.