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Finding the Fourth Proportional to 728.05, 1,086.48 and 650.20

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Solution

The fourth proportional to 728.05, 1,086.48 and 650.20 is: 970.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.05 : 1,086.48 = 650.20 : x
  2. Step 2: Convert to fraction form
    728.05/1,086.48 = 650.20/x
  3. Step 3: Cross multiply
    728.05x = 1,086.48 × 650.20
  4. Step 4: Simplify right side
    728.05x = 706,431.47
  5. Step 5: Solve for x
    x = 706,431.47/728.05
  6. Step 6: Final answer
    x = 970.30

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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.