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Finding the Fourth Proportional to 680.28, 938.83 and 381.55

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Solution

The fourth proportional to 680.28, 938.83 and 381.55 is: 526.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.28 : 938.83 = 381.55 : x
  2. Step 2: Convert to fraction form
    680.28/938.83 = 381.55/x
  3. Step 3: Cross multiply
    680.28x = 938.83 × 381.55
  4. Step 4: Simplify right side
    680.28x = 358,210.59
  5. Step 5: Solve for x
    x = 358,210.59/680.28
  6. Step 6: Final answer
    x = 526.56

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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.