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Finding the Fourth Proportional to 649.40, 895.86 and 387.38

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Solution

The fourth proportional to 649.40, 895.86 and 387.38 is: 534.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.40 : 895.86 = 387.38 : x
  2. Step 2: Convert to fraction form
    649.40/895.86 = 387.38/x
  3. Step 3: Cross multiply
    649.40x = 895.86 × 387.38
  4. Step 4: Simplify right side
    649.40x = 347,038.25
  5. Step 5: Solve for x
    x = 347,038.25/649.40
  6. Step 6: Final answer
    x = 534.40

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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.