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Finding the Fourth Proportional to 645.79, 968.70 and 388.75

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Solution

The fourth proportional to 645.79, 968.70 and 388.75 is: 583.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.79 : 968.70 = 388.75 : x
  2. Step 2: Convert to fraction form
    645.79/968.70 = 388.75/x
  3. Step 3: Cross multiply
    645.79x = 968.70 × 388.75
  4. Step 4: Simplify right side
    645.79x = 376,582.13
  5. Step 5: Solve for x
    x = 376,582.13/645.79
  6. Step 6: Final answer
    x = 583.13

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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.