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Finding the Fourth Proportional to 649.80, 975.19 and 388.99

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Solution

The fourth proportional to 649.80, 975.19 and 388.99 is: 583.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.80 : 975.19 = 388.99 : x
  2. Step 2: Convert to fraction form
    649.80/975.19 = 388.99/x
  3. Step 3: Cross multiply
    649.80x = 975.19 × 388.99
  4. Step 4: Simplify right side
    649.80x = 379,338.76
  5. Step 5: Solve for x
    x = 379,338.76/649.80
  6. Step 6: Final answer
    x = 583.78

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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.