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Finding the Fourth Proportional to 290.80, 436.20 and 265.60

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Solution

The fourth proportional to 290.80, 436.20 and 265.60 is: 398.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.80 : 436.20 = 265.60 : x
  2. Step 2: Convert to fraction form
    290.80/436.20 = 265.60/x
  3. Step 3: Cross multiply
    290.80x = 436.20 × 265.60
  4. Step 4: Simplify right side
    290.80x = 115,854.72
  5. Step 5: Solve for x
    x = 115,854.72/290.80
  6. Step 6: Final answer
    x = 398.40

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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.