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Finding the Fourth Proportional to 647.43, 893.93 and 399.30

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Solution

The fourth proportional to 647.43, 893.93 and 399.30 is: 551.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.43 : 893.93 = 399.30 : x
  2. Step 2: Convert to fraction form
    647.43/893.93 = 399.30/x
  3. Step 3: Cross multiply
    647.43x = 893.93 × 399.30
  4. Step 4: Simplify right side
    647.43x = 356,946.25
  5. Step 5: Solve for x
    x = 356,946.25/647.43
  6. Step 6: Final answer
    x = 551.33

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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.