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Finding the Fourth Proportional to 287.90, 431.55 and 123.47

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Solution

The fourth proportional to 287.90, 431.55 and 123.47 is: 185.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.90 : 431.55 = 123.47 : x
  2. Step 2: Convert to fraction form
    287.90/431.55 = 123.47/x
  3. Step 3: Cross multiply
    287.90x = 431.55 × 123.47
  4. Step 4: Simplify right side
    287.90x = 53,283.48
  5. Step 5: Solve for x
    x = 53,283.48/287.90
  6. Step 6: Final answer
    x = 185.08

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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.