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Finding the Fourth Proportional to 649.12, 896.40 and 647.80

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Solution

The fourth proportional to 649.12, 896.40 and 647.80 is: 894.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.12 : 896.40 = 647.80 : x
  2. Step 2: Convert to fraction form
    649.12/896.40 = 647.80/x
  3. Step 3: Cross multiply
    649.12x = 896.40 × 647.80
  4. Step 4: Simplify right side
    649.12x = 580,687.92
  5. Step 5: Solve for x
    x = 580,687.92/649.12
  6. Step 6: Final answer
    x = 894.58

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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.