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Finding the Fourth Proportional to 630.48, 869.28 and 397.20

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Solution

The fourth proportional to 630.48, 869.28 and 397.20 is: 547.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.48 : 869.28 = 397.20 : x
  2. Step 2: Convert to fraction form
    630.48/869.28 = 397.20/x
  3. Step 3: Cross multiply
    630.48x = 869.28 × 397.20
  4. Step 4: Simplify right side
    630.48x = 345,278.02
  5. Step 5: Solve for x
    x = 345,278.02/630.48
  6. Step 6: Final answer
    x = 547.64

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1.5x scale

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.