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Finding the Fourth Proportional to 640.68, 959.85 and 571.51

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Solution

The fourth proportional to 640.68, 959.85 and 571.51 is: 856.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.68 : 959.85 = 571.51 : x
  2. Step 2: Convert to fraction form
    640.68/959.85 = 571.51/x
  3. Step 3: Cross multiply
    640.68x = 959.85 × 571.51
  4. Step 4: Simplify right side
    640.68x = 548,559.67
  5. Step 5: Solve for x
    x = 548,559.67/640.68
  6. Step 6: Final answer
    x = 856.21

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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.