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Finding the Fourth Proportional to 280.38, 386.65 and 187.13

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Solution

The fourth proportional to 280.38, 386.65 and 187.13 is: 258.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.38 : 386.65 = 187.13 : x
  2. Step 2: Convert to fraction form
    280.38/386.65 = 187.13/x
  3. Step 3: Cross multiply
    280.38x = 386.65 × 187.13
  4. Step 4: Simplify right side
    280.38x = 72,352.51
  5. Step 5: Solve for x
    x = 72,352.51/280.38
  6. Step 6: Final answer
    x = 258.05

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.