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Finding the Fourth Proportional to 290.32, 435.62 and 128.05

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Solution

The fourth proportional to 290.32, 435.62 and 128.05 is: 192.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.32 : 435.62 = 128.05 : x
  2. Step 2: Convert to fraction form
    290.32/435.62 = 128.05/x
  3. Step 3: Cross multiply
    290.32x = 435.62 × 128.05
  4. Step 4: Simplify right side
    290.32x = 55,781.14
  5. Step 5: Solve for x
    x = 55,781.14/290.32
  6. Step 6: Final answer
    x = 192.14

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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.