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Finding the Fourth Proportional to 649.40, 896.26 and 387.40

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Solution

The fourth proportional to 649.40, 896.26 and 387.40 is: 534.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.40 : 896.26 = 387.40 : x
  2. Step 2: Convert to fraction form
    649.40/896.26 = 387.40/x
  3. Step 3: Cross multiply
    649.40x = 896.26 × 387.40
  4. Step 4: Simplify right side
    649.40x = 347,211.12
  5. Step 5: Solve for x
    x = 347,211.12/649.40
  6. Step 6: Final answer
    x = 534.66

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.