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Finding the Fourth Proportional to 647.90, 894.03 and 399.10

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Solution

The fourth proportional to 647.90, 894.03 and 399.10 is: 550.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.90 : 894.03 = 399.10 : x
  2. Step 2: Convert to fraction form
    647.90/894.03 = 399.10/x
  3. Step 3: Cross multiply
    647.90x = 894.03 × 399.10
  4. Step 4: Simplify right side
    647.90x = 356,807.37
  5. Step 5: Solve for x
    x = 356,807.37/647.90
  6. Step 6: Final answer
    x = 550.71

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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.