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Finding the Fourth Proportional to 647.75, 971.64 and 257.74

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Solution

The fourth proportional to 647.75, 971.64 and 257.74 is: 386.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.75 : 971.64 = 257.74 : x
  2. Step 2: Convert to fraction form
    647.75/971.64 = 257.74/x
  3. Step 3: Cross multiply
    647.75x = 971.64 × 257.74
  4. Step 4: Simplify right side
    647.75x = 250,428.06
  5. Step 5: Solve for x
    x = 250,428.06/647.75
  6. Step 6: Final answer
    x = 386.61

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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.