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Finding the Fourth Proportional to 630.72, 870.48 and 398.52

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Solution

The fourth proportional to 630.72, 870.48 and 398.52 is: 550.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.72 : 870.48 = 398.52 : x
  2. Step 2: Convert to fraction form
    630.72/870.48 = 398.52/x
  3. Step 3: Cross multiply
    630.72x = 870.48 × 398.52
  4. Step 4: Simplify right side
    630.72x = 346,903.69
  5. Step 5: Solve for x
    x = 346,903.69/630.72
  6. Step 6: Final answer
    x = 550.01

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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.