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Finding the Fourth Proportional to 781.89, 1,078.88 and 450.27

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Solution

The fourth proportional to 781.89, 1,078.88 and 450.27 is: 621.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    781.89 : 1,078.88 = 450.27 : x
  2. Step 2: Convert to fraction form
    781.89/1,078.88 = 450.27/x
  3. Step 3: Cross multiply
    781.89x = 1,078.88 × 450.27
  4. Step 4: Simplify right side
    781.89x = 485,785.05
  5. Step 5: Solve for x
    x = 485,785.05/781.89
  6. Step 6: Final answer
    x = 621.30

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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.