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Finding the Fourth Proportional to 647.75, 971.43 and 257.60

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Solution

The fourth proportional to 647.75, 971.43 and 257.60 is: 386.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.75 : 971.43 = 257.60 : x
  2. Step 2: Convert to fraction form
    647.75/971.43 = 257.60/x
  3. Step 3: Cross multiply
    647.75x = 971.43 × 257.60
  4. Step 4: Simplify right side
    647.75x = 250,240.37
  5. Step 5: Solve for x
    x = 250,240.37/647.75
  6. Step 6: Final answer
    x = 386.32

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.