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Finding the Fourth Proportional to 645.57, 968.51 and 255.71

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Solution

The fourth proportional to 645.57, 968.51 and 255.71 is: 383.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.57 : 968.51 = 255.71 : x
  2. Step 2: Convert to fraction form
    645.57/968.51 = 255.71/x
  3. Step 3: Cross multiply
    645.57x = 968.51 × 255.71
  4. Step 4: Simplify right side
    645.57x = 247,653.87
  5. Step 5: Solve for x
    x = 247,653.87/645.57
  6. Step 6: Final answer
    x = 383.62

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.