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Finding the Fourth Proportional to 258.50, 387.80 and 130.25

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Solution

The fourth proportional to 258.50, 387.80 and 130.25 is: 195.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.50 : 387.80 = 130.25 : x
  2. Step 2: Convert to fraction form
    258.50/387.80 = 130.25/x
  3. Step 3: Cross multiply
    258.50x = 387.80 × 130.25
  4. Step 4: Simplify right side
    258.50x = 50,510.95
  5. Step 5: Solve for x
    x = 50,510.95/258.50
  6. Step 6: Final answer
    x = 195.40

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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.