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Finding the Fourth Proportional to 640.26, 960.75 and 315.90

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Solution

The fourth proportional to 640.26, 960.75 and 315.90 is: 474.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.26 : 960.75 = 315.90 : x
  2. Step 2: Convert to fraction form
    640.26/960.75 = 315.90/x
  3. Step 3: Cross multiply
    640.26x = 960.75 × 315.90
  4. Step 4: Simplify right side
    640.26x = 303,500.93
  5. Step 5: Solve for x
    x = 303,500.93/640.26
  6. Step 6: Final answer
    x = 474.03

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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.