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Finding the Fourth Proportional to 640.48, 960.72 and 412

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Solution

The fourth proportional to 640.48, 960.72 and 412 is: 618

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.48 : 960.72 = 412 : x
  2. Step 2: Convert to fraction form
    640.48/960.72 = 412/x
  3. Step 3: Cross multiply
    640.48x = 960.72 × 412
  4. Step 4: Simplify right side
    640.48x = 395,816.64
  5. Step 5: Solve for x
    x = 395,816.64/640.48
  6. Step 6: Final answer
    x = 618

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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.