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Finding the Fourth Proportional to 645.68, 968.54 and 389

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Solution

The fourth proportional to 645.68, 968.54 and 389 is: 583.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.68 : 968.54 = 389 : x
  2. Step 2: Convert to fraction form
    645.68/968.54 = 389/x
  3. Step 3: Cross multiply
    645.68x = 968.54 × 389
  4. Step 4: Simplify right side
    645.68x = 376,762.06
  5. Step 5: Solve for x
    x = 376,762.06/645.68
  6. Step 6: Final answer
    x = 583.51

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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.