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Finding the Fourth Proportional to 289.08, 398.64 and 190.80

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Solution

The fourth proportional to 289.08, 398.64 and 190.80 is: 263.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.08 : 398.64 = 190.80 : x
  2. Step 2: Convert to fraction form
    289.08/398.64 = 190.80/x
  3. Step 3: Cross multiply
    289.08x = 398.64 × 190.80
  4. Step 4: Simplify right side
    289.08x = 76,060.51
  5. Step 5: Solve for x
    x = 76,060.51/289.08
  6. Step 6: Final answer
    x = 263.11

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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.