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Finding the Fourth Proportional to 646.72, 970.07 and 159.78

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Solution

The fourth proportional to 646.72, 970.07 and 159.78 is: 239.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.72 : 970.07 = 159.78 : x
  2. Step 2: Convert to fraction form
    646.72/970.07 = 159.78/x
  3. Step 3: Cross multiply
    646.72x = 970.07 × 159.78
  4. Step 4: Simplify right side
    646.72x = 154,997.78
  5. Step 5: Solve for x
    x = 154,997.78/646.72
  6. Step 6: Final answer
    x = 239.67

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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.