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Finding the Fourth Proportional to 399.80, 598.90 and 255

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Solution

The fourth proportional to 399.80, 598.90 and 255 is: 381.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.80 : 598.90 = 255 : x
  2. Step 2: Convert to fraction form
    399.80/598.90 = 255/x
  3. Step 3: Cross multiply
    399.80x = 598.90 × 255
  4. Step 4: Simplify right side
    399.80x = 152,719.50
  5. Step 5: Solve for x
    x = 152,719.50/399.80
  6. Step 6: Final answer
    x = 381.99

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.