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Finding the Fourth Proportional to 290.79, 400.86 and 208.08

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Solution

The fourth proportional to 290.79, 400.86 and 208.08 is: 286.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.79 : 400.86 = 208.08 : x
  2. Step 2: Convert to fraction form
    290.79/400.86 = 208.08/x
  3. Step 3: Cross multiply
    290.79x = 400.86 × 208.08
  4. Step 4: Simplify right side
    290.79x = 83,410.95
  5. Step 5: Solve for x
    x = 83,410.95/290.79
  6. Step 6: Final answer
    x = 286.84

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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.