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Finding the Fourth Proportional to 388.99, 536.79 and 290.80

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Solution

The fourth proportional to 388.99, 536.79 and 290.80 is: 401.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.99 : 536.79 = 290.80 : x
  2. Step 2: Convert to fraction form
    388.99/536.79 = 290.80/x
  3. Step 3: Cross multiply
    388.99x = 536.79 × 290.80
  4. Step 4: Simplify right side
    388.99x = 156,098.53
  5. Step 5: Solve for x
    x = 156,098.53/388.99
  6. Step 6: Final answer
    x = 401.29

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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.