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Finding the Fourth Proportional to 640.77, 960.47 and 275.25

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Solution

The fourth proportional to 640.77, 960.47 and 275.25 is: 412.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.77 : 960.47 = 275.25 : x
  2. Step 2: Convert to fraction form
    640.77/960.47 = 275.25/x
  3. Step 3: Cross multiply
    640.77x = 960.47 × 275.25
  4. Step 4: Simplify right side
    640.77x = 264,369.37
  5. Step 5: Solve for x
    x = 264,369.37/640.77
  6. Step 6: Final answer
    x = 412.58

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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.