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Finding the Fourth Proportional to 649.67, 972.76 and 388.45

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Solution

The fourth proportional to 649.67, 972.76 and 388.45 is: 581.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.67 : 972.76 = 388.45 : x
  2. Step 2: Convert to fraction form
    649.67/972.76 = 388.45/x
  3. Step 3: Cross multiply
    649.67x = 972.76 × 388.45
  4. Step 4: Simplify right side
    649.67x = 377,864.12
  5. Step 5: Solve for x
    x = 377,864.12/649.67
  6. Step 6: Final answer
    x = 581.62

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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.