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Finding the Fourth Proportional to 824.80, 1,237.20 and 630.40

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Solution

The fourth proportional to 824.80, 1,237.20 and 630.40 is: 945.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    824.80 : 1,237.20 = 630.40 : x
  2. Step 2: Convert to fraction form
    824.80/1,237.20 = 630.40/x
  3. Step 3: Cross multiply
    824.80x = 1,237.20 × 630.40
  4. Step 4: Simplify right side
    824.80x = 779,930.88
  5. Step 5: Solve for x
    x = 779,930.88/824.80
  6. Step 6: Final answer
    x = 945.60

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.