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Finding the Fourth Proportional to 638.40, 952.40 and 630.20

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Solution

The fourth proportional to 638.40, 952.40 and 630.20 is: 940.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.40 : 952.40 = 630.20 : x
  2. Step 2: Convert to fraction form
    638.40/952.40 = 630.20/x
  3. Step 3: Cross multiply
    638.40x = 952.40 × 630.20
  4. Step 4: Simplify right side
    638.40x = 600,202.48
  5. Step 5: Solve for x
    x = 600,202.48/638.40
  6. Step 6: Final answer
    x = 940.17

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.