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Finding the Fourth Proportional to 290.47, 435.71 and 128.17

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Solution

The fourth proportional to 290.47, 435.71 and 128.17 is: 192.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.47 : 435.71 = 128.17 : x
  2. Step 2: Convert to fraction form
    290.47/435.71 = 128.17/x
  3. Step 3: Cross multiply
    290.47x = 435.71 × 128.17
  4. Step 4: Simplify right side
    290.47x = 55,843.36
  5. Step 5: Solve for x
    x = 55,843.36/290.47
  6. Step 6: Final answer
    x = 192.25

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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.