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Finding the Fourth Proportional to 647.31, 970.94 and 208.58

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Solution

The fourth proportional to 647.31, 970.94 and 208.58 is: 312.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.31 : 970.94 = 208.58 : x
  2. Step 2: Convert to fraction form
    647.31/970.94 = 208.58/x
  3. Step 3: Cross multiply
    647.31x = 970.94 × 208.58
  4. Step 4: Simplify right side
    647.31x = 202,513.16
  5. Step 5: Solve for x
    x = 202,513.16/647.31
  6. Step 6: Final answer
    x = 312.85

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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.