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Finding the Fourth Proportional to 646.80, 970.19 and 159.86

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Solution

The fourth proportional to 646.80, 970.19 and 159.86 is: 239.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.80 : 970.19 = 159.86 : x
  2. Step 2: Convert to fraction form
    646.80/970.19 = 159.86/x
  3. Step 3: Cross multiply
    646.80x = 970.19 × 159.86
  4. Step 4: Simplify right side
    646.80x = 155,088.92
  5. Step 5: Solve for x
    x = 155,088.92/646.80
  6. Step 6: Final answer
    x = 239.78

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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.