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Finding the Fourth Proportional to 647.12, 970.11 and 386.78

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Solution

The fourth proportional to 647.12, 970.11 and 386.78 is: 579.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.12 : 970.11 = 386.78 : x
  2. Step 2: Convert to fraction form
    647.12/970.11 = 386.78/x
  3. Step 3: Cross multiply
    647.12x = 970.11 × 386.78
  4. Step 4: Simplify right side
    647.12x = 375,214.30
  5. Step 5: Solve for x
    x = 375,214.30/647.12
  6. Step 6: Final answer
    x = 579.82

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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.