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Finding the Fourth Proportional to 728.60, 986.85 and 728.60

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Solution

The fourth proportional to 728.60, 986.85 and 728.60 is: 986.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.60 : 986.85 = 728.60 : x
  2. Step 2: Convert to fraction form
    728.60/986.85 = 728.60/x
  3. Step 3: Cross multiply
    728.60x = 986.85 × 728.60
  4. Step 4: Simplify right side
    728.60x = 719,018.91
  5. Step 5: Solve for x
    x = 719,018.91/728.60
  6. Step 6: Final answer
    x = 986.85

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.35) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.