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Finding the Fourth Proportional to 641.26, 961.99 and 208.31

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Solution

The fourth proportional to 641.26, 961.99 and 208.31 is: 312.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.26 : 961.99 = 208.31 : x
  2. Step 2: Convert to fraction form
    641.26/961.99 = 208.31/x
  3. Step 3: Cross multiply
    641.26x = 961.99 × 208.31
  4. Step 4: Simplify right side
    641.26x = 200,394.02
  5. Step 5: Solve for x
    x = 200,394.02/641.26
  6. Step 6: Final answer
    x = 312.50

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1.5x scale

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.