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Finding the Fourth Proportional to 388.86, 536.31 and 290.70

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Solution

The fourth proportional to 388.86, 536.31 and 290.70 is: 400.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.86 : 536.31 = 290.70 : x
  2. Step 2: Convert to fraction form
    388.86/536.31 = 290.70/x
  3. Step 3: Cross multiply
    388.86x = 536.31 × 290.70
  4. Step 4: Simplify right side
    388.86x = 155,905.32
  5. Step 5: Solve for x
    x = 155,905.32/388.86
  6. Step 6: Final answer
    x = 400.93

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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.