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Finding the Fourth Proportional to 290.10, 400.35 and 165.78

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Solution

The fourth proportional to 290.10, 400.35 and 165.78 is: 228.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.10 : 400.35 = 165.78 : x
  2. Step 2: Convert to fraction form
    290.10/400.35 = 165.78/x
  3. Step 3: Cross multiply
    290.10x = 400.35 × 165.78
  4. Step 4: Simplify right side
    290.10x = 66,369.19
  5. Step 5: Solve for x
    x = 66,369.19/290.10
  6. Step 6: Final answer
    x = 228.78

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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.