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Finding the Fourth Proportional to 680.60, 939.30 and 400.97

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Solution

The fourth proportional to 680.60, 939.30 and 400.97 is: 553.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.60 : 939.30 = 400.97 : x
  2. Step 2: Convert to fraction form
    680.60/939.30 = 400.97/x
  3. Step 3: Cross multiply
    680.60x = 939.30 × 400.97
  4. Step 4: Simplify right side
    680.60x = 376,631.12
  5. Step 5: Solve for x
    x = 376,631.12/680.60
  6. Step 6: Final answer
    x = 553.38

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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.