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Finding the Fourth Proportional to 647.69, 970.89 and 257.56

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Solution

The fourth proportional to 647.69, 970.89 and 257.56 is: 386.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.69 : 970.89 = 257.56 : x
  2. Step 2: Convert to fraction form
    647.69/970.89 = 257.56/x
  3. Step 3: Cross multiply
    647.69x = 970.89 × 257.56
  4. Step 4: Simplify right side
    647.69x = 250,062.43
  5. Step 5: Solve for x
    x = 250,062.43/647.69
  6. Step 6: Final answer
    x = 386.08

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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.