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Finding the Fourth Proportional to 647.40, 893.34 and 398.60

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Solution

The fourth proportional to 647.40, 893.34 and 398.60 is: 550.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.40 : 893.34 = 398.60 : x
  2. Step 2: Convert to fraction form
    647.40/893.34 = 398.60/x
  3. Step 3: Cross multiply
    647.40x = 893.34 × 398.60
  4. Step 4: Simplify right side
    647.40x = 356,085.32
  5. Step 5: Solve for x
    x = 356,085.32/647.40
  6. Step 6: Final answer
    x = 550.02

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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.