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Finding the Fourth Proportional to 646.78, 970.31 and 208.07

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Solution

The fourth proportional to 646.78, 970.31 and 208.07 is: 312.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.78 : 970.31 = 208.07 : x
  2. Step 2: Convert to fraction form
    646.78/970.31 = 208.07/x
  3. Step 3: Cross multiply
    646.78x = 970.31 × 208.07
  4. Step 4: Simplify right side
    646.78x = 201,889.76
  5. Step 5: Solve for x
    x = 201,889.76/646.78
  6. Step 6: Final answer
    x = 312.14

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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.