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Finding the Fourth Proportional to 647.45, 970.48 and 257.66

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Solution

The fourth proportional to 647.45, 970.48 and 257.66 is: 386.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.45 : 970.48 = 257.66 : x
  2. Step 2: Convert to fraction form
    647.45/970.48 = 257.66/x
  3. Step 3: Cross multiply
    647.45x = 970.48 × 257.66
  4. Step 4: Simplify right side
    647.45x = 250,053.88
  5. Step 5: Solve for x
    x = 250,053.88/647.45
  6. Step 6: Final answer
    x = 386.21

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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.