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Finding the Fourth Proportional to 640.23, 959.78 and 531.45

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Solution

The fourth proportional to 640.23, 959.78 and 531.45 is: 796.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.23 : 959.78 = 531.45 : x
  2. Step 2: Convert to fraction form
    640.23/959.78 = 531.45/x
  3. Step 3: Cross multiply
    640.23x = 959.78 × 531.45
  4. Step 4: Simplify right side
    640.23x = 510,075.08
  5. Step 5: Solve for x
    x = 510,075.08/640.23
  6. Step 6: Final answer
    x = 796.71

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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.