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Finding the Fourth Proportional to 259.29, 388.80 and 129.18

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Solution

The fourth proportional to 259.29, 388.80 and 129.18 is: 193.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.29 : 388.80 = 129.18 : x
  2. Step 2: Convert to fraction form
    259.29/388.80 = 129.18/x
  3. Step 3: Cross multiply
    259.29x = 388.80 × 129.18
  4. Step 4: Simplify right side
    259.29x = 50,225.18
  5. Step 5: Solve for x
    x = 50,225.18/259.29
  6. Step 6: Final answer
    x = 193.70

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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.