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Finding the Fourth Proportional to 640.64, 960 and 255.68

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Solution

The fourth proportional to 640.64, 960 and 255.68 is: 383.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.64 : 960 = 255.68 : x
  2. Step 2: Convert to fraction form
    640.64/960 = 255.68/x
  3. Step 3: Cross multiply
    640.64x = 960 × 255.68
  4. Step 4: Simplify right side
    640.64x = 245,452.80
  5. Step 5: Solve for x
    x = 245,452.80/640.64
  6. Step 6: Final answer
    x = 383.14

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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.