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Finding the Fourth Proportional to 646.89, 970.25 and 208.19

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Solution

The fourth proportional to 646.89, 970.25 and 208.19 is: 312.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.89 : 970.25 = 208.19 : x
  2. Step 2: Convert to fraction form
    646.89/970.25 = 208.19/x
  3. Step 3: Cross multiply
    646.89x = 970.25 × 208.19
  4. Step 4: Simplify right side
    646.89x = 201,990.46
  5. Step 5: Solve for x
    x = 201,990.46/646.89
  6. Step 6: Final answer
    x = 312.25

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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.