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Finding the Fourth Proportional to 388.80, 536.22 and 290.79

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Solution

The fourth proportional to 388.80, 536.22 and 290.79 is: 401.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.80 : 536.22 = 290.79 : x
  2. Step 2: Convert to fraction form
    388.80/536.22 = 290.79/x
  3. Step 3: Cross multiply
    388.80x = 536.22 × 290.79
  4. Step 4: Simplify right side
    388.80x = 155,927.41
  5. Step 5: Solve for x
    x = 155,927.41/388.80
  6. Step 6: Final answer
    x = 401.05

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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.