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Finding the Fourth Proportional to 279.90, 386.25 and 155.55

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Solution

The fourth proportional to 279.90, 386.25 and 155.55 is: 214.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.90 : 386.25 = 155.55 : x
  2. Step 2: Convert to fraction form
    279.90/386.25 = 155.55/x
  3. Step 3: Cross multiply
    279.90x = 386.25 × 155.55
  4. Step 4: Simplify right side
    279.90x = 60,081.19
  5. Step 5: Solve for x
    x = 60,081.19/279.90
  6. Step 6: Final answer
    x = 214.65

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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.