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Finding the Fourth Proportional to 683.78, 943.41 and 421.70

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Solution

The fourth proportional to 683.78, 943.41 and 421.70 is: 581.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    683.78 : 943.41 = 421.70 : x
  2. Step 2: Convert to fraction form
    683.78/943.41 = 421.70/x
  3. Step 3: Cross multiply
    683.78x = 943.41 × 421.70
  4. Step 4: Simplify right side
    683.78x = 397,836.00
  5. Step 5: Solve for x
    x = 397,836.00/683.78
  6. Step 6: Final answer
    x = 581.82

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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.