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Finding the Fourth Proportional to 646.91, 970.41 and 208.21

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Solution

The fourth proportional to 646.91, 970.41 and 208.21 is: 312.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.91 : 970.41 = 208.21 : x
  2. Step 2: Convert to fraction form
    646.91/970.41 = 208.21/x
  3. Step 3: Cross multiply
    646.91x = 970.41 × 208.21
  4. Step 4: Simplify right side
    646.91x = 202,049.07
  5. Step 5: Solve for x
    x = 202,049.07/646.91
  6. Step 6: Final answer
    x = 312.33

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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.